Cleanup clippy warnings

warning: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
 --> src/output/escape.rs:4:1
  |
4 | pub fn escape<'a>(string: String, bits: &mut Vec<ANSIString<'a>>, good: Style, bad: Style) {
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  |

warning: this lifetime isn't used in the function definition
 --> src/output/escape.rs:4:15
  |
4 | pub fn escape<'a>(string: String, bits: &mut Vec<ANSIString<'_>>, good: Style, bad: Style) {
  |               ^^
  |

warning: single-character string constant used as pattern
   --> src/output/table.rs:310:41
    |
310 |                     if file.starts_with(":") {
    |                                         ^^^ help: try using a `char` instead: `':'`
    |

warning: single-character string constant used as pattern
   --> src/output/table.rs:310:41
    |
310 |                     if file.starts_with(":") {
    |                                         ^^^ help: try using a `char` instead: `':'`
    |

warning: methods called `new` usually return `Self`
  --> src/output/render/git.rs:38:5
   |
38 |     fn new(&self) -> Style;
   |     ^^^^^^^^^^^^^^^^^^^^^^^
   |

warning: this lifetime isn't used in the function definition
  --> src/output/icons.rs:40:22
   |
40 | pub fn iconify_style<'a>(style: Style) -> Style {
   |                      ^^
   |

warning: lint `clippy::find_map` has been removed: this lint has been replaced by `manual_find_map`, a more specific lint
  --> src/main.rs:11:10
   |
11 | #![allow(clippy::find_map)]
   |          ^^^^^^^^^^^^^^^^
   |

warning: redundant else block
   --> src/fs/dir.rs:124:18
    |
124 |               else {
    |  __________________^
125 | |                 return None
126 | |             }
    | |_____________^
    |

warning: redundant else block
  --> src/options/view.rs:60:18
   |
60 |               else {
   |  __________________^
61 | |                 // the --tree case is handled by the DirAction parser later
62 | |                 return Ok(Self::Details(details));
63 | |             }
   | |_____________^
   |

warning: all variants have the same postfix: `Bytes`
   --> src/output/table.rs:170:1
    |
170 | / pub enum SizeFormat {
171 | |
172 | |     /// Format the file size using **decimal** prefixes, such as “kilo”,
173 | |     /// “mega”, or “giga”.
...   |
181 | |     JustBytes,
182 | | }
    | |_^
    |

warning: all variants have the same postfix: `Bytes`
   --> src/output/table.rs:171:1
    |
171 | / pub enum SizeFormat {
172 | |
173 | |     /// Format the file size using **decimal** prefixes, such as “kilo”,
174 | |     /// “mega”, or “giga”.
...   |
182 | |     JustBytes,
183 | | }
    | |_^
    |

warning: useless use of `format!`
   --> src/options/mod.rs:181:50
    |
181 |               return Err(OptionsError::Unsupported(format!(
    |  __________________________________________________^
182 | |                 "Options --git and --git-ignore can't be used because `git` feature was disabled in this build of exa"
183 | |             )));
    | |_____________^ help: consider using `.to_string()`: `"Options --git and --git-ignore can't be used because `git` feature was disabled in this build of exa".to_string()`
    |

warning: stripping a prefix manually
   --> src/fs/filter.rs:287:33
    |
287 |         if n.starts_with('.') { &n[1..] }
    |                                 ^^^^^^^
    |

warning: case-sensitive file extension comparison
  --> src/info/filetype.rs:24:19
   |
24 |         file.name.ends_with(".ninja") ||
   |                   ^^^^^^^^^^^^^^^^^^^
   |

10 files changed, 19 insertions, 15 deletions

diff --git a/src/fs/dir.rs b/src/fs/dir.rs
index 7f7b067..1a6ce01 100644
--- a/src/fs/dir.rs
+++ b/src/fs/dir.rs
@@ -121,9 +121,8 @@ impl<'dir, 'ig> Files<'dir, 'ig> {
                 return Some(File::from_args(path.clone(), self.dir, filename)
                                  .map_err(|e| (path.clone(), e)))
             }
-            else {
-                return None
-            }
+
+            return None
         }
     }
 }
diff --git a/src/fs/filter.rs b/src/fs/filter.rs
index 4cd6ad2..08770e6 100644
--- a/src/fs/filter.rs
+++ b/src/fs/filter.rs
@@ -284,8 +284,10 @@ impl SortField {
     }
 
     fn strip_dot(n: &str) -> &str {
-        if n.starts_with('.') { &n[1..] }
-                         else { n }
+        match n.strip_prefix('.') {
+            Some(s) => s,
+            None    => n,
+        }
     }
 }
 
diff --git a/src/info/filetype.rs b/src/info/filetype.rs
index 8f54281..1def7a2 100644
--- a/src/info/filetype.rs
+++ b/src/info/filetype.rs
@@ -19,6 +19,7 @@ impl FileExtensions {
     /// An “immediate” file is something that can be run or activated somehow
     /// in order to kick off the build of a project. It’s usually only present
     /// in directories full of source code.
+    #[allow(clippy::case_sensitive_file_extension_comparisons)]
     fn is_immediate(&self, file: &File<'_>) -> bool {
         file.name.to_lowercase().starts_with("readme") ||
         file.name.ends_with(".ninja") ||
diff --git a/src/main.rs b/src/main.rs
index 84f36b7..4d762b5 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -8,7 +8,6 @@
 
 #![warn(clippy::all, clippy::pedantic)]
 #![allow(clippy::enum_glob_use)]
-#![allow(clippy::find_map)]
 #![allow(clippy::map_unwrap_or)]
 #![allow(clippy::match_same_arms)]
 #![allow(clippy::missing_const_for_fn)]
@@ -19,6 +18,7 @@
 #![allow(clippy::option_if_let_else)]
 #![allow(clippy::too_many_lines)]
 #![allow(clippy::unused_self)]
+#![allow(clippy::upper_case_acronyms)]
 #![allow(clippy::wildcard_imports)]
 
 use std::env;
diff --git a/src/options/mod.rs b/src/options/mod.rs
index 747213b..528ba43 100644
--- a/src/options/mod.rs
+++ b/src/options/mod.rs
@@ -178,7 +178,7 @@ impl Options {
     fn deduce<V: Vars>(matches: &MatchedFlags<'_>, vars: &V) -> Result<Self, OptionsError> {
         if cfg!(not(feature = "git")) &&
                 matches.has_where_any(|f| f.matches(&flags::GIT) || f.matches(&flags::GIT_IGNORE)).is_some() {
-            return Err(OptionsError::Unsupported(format!(
+            return Err(OptionsError::Unsupported(String::from(
                 "Options --git and --git-ignore can't be used because `git` feature was disabled in this build of exa"
             )));
         }
diff --git a/src/options/view.rs b/src/options/view.rs
index 6d7abac..fe42838 100644
--- a/src/options/view.rs
+++ b/src/options/view.rs
@@ -57,10 +57,9 @@ impl Mode {
                 let grid_details = grid_details::Options { grid, details, row_threshold };
                 return Ok(Self::GridDetails(grid_details));
             }
-            else {
-                // the --tree case is handled by the DirAction parser later
-                return Ok(Self::Details(details));
-            }
+
+            // the --tree case is handled by the DirAction parser later
+            return Ok(Self::Details(details));
         }
 
         Self::strict_check_long_flags(matches)?;
diff --git a/src/output/escape.rs b/src/output/escape.rs
index b4e801d..4c9f86c 100644
--- a/src/output/escape.rs
+++ b/src/output/escape.rs
@@ -1,7 +1,7 @@
 use ansi_term::{ANSIString, Style};
 
 
-pub fn escape<'a>(string: String, bits: &mut Vec<ANSIString<'a>>, good: Style, bad: Style) {
+pub fn escape(string: String, bits: &mut Vec<ANSIString<'_>>, good: Style, bad: Style) {
     if string.chars().all(|c| c >= 0x20 as char && c != 0x7f as char) {
         bits.push(good.paint(string));
         return;
diff --git a/src/output/icons.rs b/src/output/icons.rs
index 8c024dc..eea0286 100644
--- a/src/output/icons.rs
+++ b/src/output/icons.rs
@@ -37,7 +37,7 @@ impl Icons {
 /// - If neither is set, just use the default style.
 /// - Attributes such as bold or underline should not be used to paint the
 ///   icon, as they can make it look weird.
-pub fn iconify_style<'a>(style: Style) -> Style {
+pub fn iconify_style(style: Style) -> Style {
     style.background.or(style.foreground)
          .map(Style::from)
          .unwrap_or_default()
diff --git a/src/output/render/git.rs b/src/output/render/git.rs
index 7ec9589..3740d40 100644
--- a/src/output/render/git.rs
+++ b/src/output/render/git.rs
@@ -35,6 +35,7 @@ impl f::GitStatus {
 
 pub trait Colours {
     fn not_modified(&self) -> Style;
+    #[allow(clippy::new_ret_no_self)]
     fn new(&self) -> Style;
     fn modified(&self) -> Style;
     fn deleted(&self) -> Style;
diff --git a/src/output/table.rs b/src/output/table.rs
index fbe716c..1680ec7 100644
--- a/src/output/table.rs
+++ b/src/output/table.rs
@@ -28,6 +28,7 @@ pub struct Options {
 }
 
 /// Extra columns to display in the table.
+#[allow(clippy::struct_excessive_bools)]
 #[derive(PartialEq, Debug, Copy, Clone)]
 pub struct Columns {
 
@@ -166,6 +167,7 @@ impl Column {
 
 
 /// Formatting options for file sizes.
+#[allow(clippy::pub_enum_variant_names)]
 #[derive(PartialEq, Debug, Copy, Clone)]
 pub enum SizeFormat {
 
@@ -303,11 +305,11 @@ impl Environment {
 fn determine_time_zone() -> TZResult<TimeZone> {
     if let Ok(file) = env::var("TZ") {
         TimeZone::from_file({
-            if file.starts_with("/") {
+            if file.starts_with('/') {
                 file
             } else {
                 format!("/usr/share/zoneinfo/{}", {
-                    if file.starts_with(":") {
+                    if file.starts_with(':') {
                         file.replacen(":", "", 1)
                     } else {
                         file