deps: update to regex 1.0.1

This causes SIMD to kick in automatically when compiling with stable
Rust 1.27+.

We also update the README to describe the current state of things.

Thanks to @hartley for pointing this out:
https://twitter.com/hartley/status/1009950392862453760

2 files changed, 15 insertions, 14 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 7ba6d178..df657d03 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -102,7 +102,7 @@ dependencies = [
  "glob 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "memchr 2.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "regex 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "regex 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -111,7 +111,7 @@ version = "0.1.8"
 dependencies = [
  "log 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "memchr 2.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "regex 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "regex 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "regex-syntax 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -124,7 +124,7 @@ dependencies = [
  "lazy_static 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "memchr 2.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "regex 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "regex 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "same-file 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "tempdir 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "thread_local 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -200,7 +200,7 @@ dependencies = [
 
 [[package]]
 name = "regex"
-version = "1.0.0"
+version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "aho-corasick 0.6.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -243,7 +243,7 @@ dependencies = [
  "memchr 2.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "memmap 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "num_cpus 1.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "regex 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "regex 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "same-file 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "termcolor 0.3.6",
  "winapi 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -396,7 +396,7 @@ dependencies = [
 "checksum rand 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)" = "eba5f8cb59cc50ed56be8880a5c7b496bfd9bd26394e176bc67884094145c2c5"
 "checksum redox_syscall 0.1.37 (registry+https://github.com/rust-lang/crates.io-index)" = "0d92eecebad22b767915e4d529f89f28ee96dbbf5a4810d2b844373f136417fd"
 "checksum redox_termios 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "7e891cfe48e9100a70a3b6eb652fef28920c117d366339687bd5576160db0f76"
-"checksum regex 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "75ecf88252dce580404a22444fc7d626c01815debba56a7f4f536772a5ff19d3"
+"checksum regex 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)" = "13c93d55961981ba9226a213b385216f83ab43bd6ac53ab16b2eeb47e337cf4e"
 "checksum regex-syntax 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)" = "8f1ac0f60d675cc6cf13a20ec076568254472551051ad5dd050364d70671bf6b"
 "checksum remove_dir_all 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)" = "3488ba1b9a2084d38645c4c08276a1752dcbf2c7130d74f1569681ad5d2799c5"
 "checksum same-file 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "cfb6eded0b06a0b512c8ddbcf04089138c9b4362c2f696f3c3d76039d68f3637"
diff --git a/README.md b/README.md
index efc41683..eff247a7 100644
--- a/README.md
+++ b/README.md
@@ -306,13 +306,8 @@ If you're a **Rust programmer**, ripgrep can be installed with `cargo`.
 $ cargo install ripgrep
 ```
 
-If you're using Rust nightly, then use
-
-```
-$ cargo install ripgrep --features unstable
-```
-
-to get SIMD optimizations.
+When compiling with Rust 1.27 or newer, this will automatically enable SIMD
+optimizations for search.
 
 ripgrep isn't currently in any other package repositories.
 [I'd like to change that](https://github.com/BurntSushi/ripgrep/issues/10).
@@ -333,7 +328,7 @@ $ ./target/release/rg --version
 ```
 
 If you have a Rust nightly compiler and a recent Intel CPU, then you can enable
-optional SIMD acceleration like so:
+additional optional SIMD acceleration like so:
 
 ```
 RUSTFLAGS="-C target-cpu=native" cargo build --release --features 'simd-accel avx-accel'
@@ -343,6 +338,12 @@ If your machine doesn't support AVX instructions, then simply remove
 `avx-accel` from the features list. Similarly for SIMD (which corresponds
 roughly to SSE instructions).
 
+The `simd-accel` and `avx-accel` features enable SIMD support in certain
+ripgrep dependencies (responsible for counting lines and transcoding). They
+are not necessary to get SIMD optimizations for search; those are enabled
+automatically. Hopefully, some day, the `simd-accel` and `avx-accel` features
+will similarly become unnecessary.
+
 
 ### Running tests