Add a "log" implementation

[Smolations]

We currently have no implementation to make access of git logs easier. We should create a wrapper for this which allows for users to:

• Retrieve the last n log statements, with the option to view them on a single line (--oneline)
• Search log commit messages for any number of strings
• Have an option to run a diff between any two hashes in log statements OR a hash from a log statement and HEAD

This is a preliminary list. Features may change based on the experience each of us has with using git log.