Test functions name as tests files name must begin with test in order to be run by manage.py test

Created the class Lodel.utils.mlstring.MlString needed by EditorialModel.lib.component.EmComponent
The first test pass ! =)

Lodel/sttings/__init__.py wasn't able to import files when called by manage.py
Renaming em to EditorialModel and moved Em* objects to EditorialModel/lib
Adding a first test (that do not pass because of syntax errors in Em* classes)