Improve show commit module

This change refactors and improves the show commit module. This change
added:

- key bindings/help displayed on the last line
- list of number of files changed as well as the number of additions and
deletions
- git configuration for renames, rename_limit and copies now respected
- full help page

This change refactored:

- input handling to be specific to the show commit module
- rewritten how git diff information is queried from the git2-rs
bindings
- new ViewDataBuilder struct for building the view lines

1 files changed, 16 insertions, 0 deletions

diff --git a/README.md b/README.md
index e9a477f..68ae779 100644
--- a/README.md
+++ b/README.md
@@ -106,6 +106,22 @@ instead. String values are case-insensitive.
 git config --global interactive-rebase-tool.foregroundColor black
 ```
 
+#### Git configuration
+
+Some values from your Git Config are directly used by this application.
+
+| Key                                   | Description |
+| ------------------------------------- | ----------- |
+| [`core.commentChar`][coreCommentChar] | Read when reading the TODO file to excluded commented lines |
+| [`core.editor`][coreEditor]           | Read when deciding what editor to open when trigger the external editor |
+| [`diff.renames`][diffRenames]         | Used by show commit when generating a diff |
+| [`diff.renameLimit`][diffRenameLimit] | Used by show commit when generating a diff |
+
+[coreCommentChar]:https://git-scm.com/docs/git-config#Documentation/git-config.txt-corecommentChar
+[coreEditor]:https://git-scm.com/docs/git-config#Documentation/git-config.txt-coreeditor
+[diffRenames]:https://git-scm.com/docs/diff-config/#Documentation/diff-config.txt-diffrenames
+[diffRenameLimit]:https://git-scm.com/docs/diff-config/#Documentation/diff-config.txt-diffrenameLimit
+
 #### General
 
 | Key                        | Default | Type   | Description |