Merge branch 'less-chatty-hipchat-intergation' into 'master'

Less chatty HipChat intergation

The HipChat integration is noisy. In our team it constantly overwhelms the channel with a lot of commits or the bodies of their messages. It's very easy to loose the actual conversation in the midst of this.

This request does two things:

* Limit the number of shown commits on every push
* Display only the first line (the subject) of each commit messages

We tried it and found it was nicer for us 

See merge request !159