mnit_simple : Refactoring of android modules tests

All mnit_simple tests have been refactored to multiple test files allowing to run tests on a module basis. A new folder named `tests` has been created containing these tests. Each test now has a Makefile entry based on that rule : `test_Module_Name`.  
Alexis tient à ce qu'il reste dans le même module qu'il a dit plus haut. Je ne m'en mèle pas.