Import all the data from Github API for repo

I think we should also have a `repo` app(as we will be having [issue](https://github.com/coala/community/issues/83) and [pullrequest](https://github.com/coala/community/issues/83) app) which collects all the data Github API provides for a repo see https://developer.github.com/v3/repos/
We could do some awesome things with these data in future and also might be helpful to do analysis in [Newcomer metrics and gamification](http://projects.coala.io/#/projects?project=newcomer_metrics_and_gamification&lang=en) project