Latest commit message for each repo

[nathandao]

In order to do this, we'll need to add an additional "limit" params to the api.

• From my first iperssion, since the web API passes all params through to Ginatra::Repository, we'll only need to add the "limit" param option there.
• Once the web API is available, add an additional row to the RepoInfo react component to pull the latest commit message (possibly with author name as well?)

[nathandao]

"limit" param was added by @rihards in #11 .

Now just need to add the front-end part in Reactjs :)