Stats class

[mdespuits]

Begin statistics calculation into it's own class. Just inherit from Hash and use the existing framework for statistics calculation until we move it into it's own object.

[mdespuits]

@kevinjalbert What do you think? Haven't heard anything... 😉

[coveralls]

Coverage remained the same when pulling a0a2277 on statistics-class into 75605f9 on master.

[mdespuits]

@kevinjalbert Still wanting to continue work on this. Any thoughts?

[kevinjalbert]

@mattdbridges Yep, I think having a Statistics class is a good idea other then just using a modified Hash. Just trying to work out #54, I think when we have that in place we could better use the commit-domain object for the statistics.

[coveralls]

Changes Unknown when pulling 3956892 on statistics-class into * on master*.

[coveralls]

Changes Unknown when pulling ebd6b89 on statistics-class into * on master*.

[kevinjalbert]

@mdespuits I rebased and fixed up Travis CI's config.

Seems like the specs still pass, and functionally this returns the same output on an example repo I have. I plan to merge this PR in as the concept of a stats class will be helpful in the future (if this project so happens to see more development).

As seen I haven't been activity developing on this project for a while, so I'm just cleaning out issues and PRs currently.