Add a unitary test system

[loolmeh]

As the amount of code is growing and as we're now several users to contribute, it can be good to add non-regression test and so, (maybe there's a framework to do so within cakephp, if not a set of python script can do the job ) to automatically test hazardous input, such as sql injection tentative and so, but also for essential features such as translations , favoriting and so, that way it will make prerelease job much more easier and safe