Obligate tests and reviews, before merging into master

[stefanpolzer]

There are so many small issues the last month, because every one can commit something and it is landing untested in the master branch.

I suggest a testing work flow (e.g. Unit Test), before a commit is considered to be merged into the master branch.
Secondary I suggest that at least two persons should review or test a commit manualy, before the commit is merged into the master branch.

[stefanpolzer]

@zirnipa I assume/see that this is now done by you and @mdaskalov so I close this for now.