Adding GitCommit class representing a git commit

Up until now, gitlint only had to notion of a git commit message.
This commit adds the GitCommit class which stores both the commit
message, and meta-info related to the commit (author, date, commit id, etc).

This will allow us to write gitlint rules based on meta-info (e.g.
restrictions on the author email address format).

For now, the commit_msg property of the GitContext class just refers to
the commit_msg of the last commit. This was done as a temporary measure to
reduce the amount of code change in a single commit.

Also made some minor documentation sites updates (not published yet).

1 files changed, 4 insertions, 1 deletions

diff --git a/docs/index.md b/docs/index.md
index e630b78..3b1107b 100644
--- a/docs/index.md
+++ b/docs/index.md
@@ -46,7 +46,10 @@ NOTE: The returned exit code equals the number of errors found. [Some exit codes
 
 For a list of available rules and their configuration options, have a look at the [Rules](rules.md) page.
 
-You can modify verbosity using the ```-v``` flag, like so:
+The [Configuration](configuration.md) page explains how you can modify gitlint's runtime behavior via command-line
+flags, a ```.gitlint``` configuration file or on a per commit basis.
+
+As a simple example, you can modify gitlint's verbosity using the ```-v``` flag, like so:
 ```bash
 $ cat examples/commit-message-2 | gitlint -v
 1: T1