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`.  
Ca serait p'tet mieux que test_all soit le make android, c'est a dire celui envoyé sur le depot fdroid