Subject: Protect commits to master with CircleCI ...

Hi folks,

I'd like to share a video [1], where Daniel Shiffman demonstrates how to
use CirlceCI [2] with github:
He uses a JavaScript demo project, but it should also work with Java.

In short: Github allows to be configured such that it rejects a commit
to e.g. 'master', if this commit would fail any JUnit tests.

With some initial effort, this could be very handy for us (Isis).

Cheers, Andi