EmComponent.create() now takes keywords arguments corresponding to the _fields property of the calling class

WARNING !!! Hardcoded rank = -1 at component creation and Hardcoded 0 as default value for EmClass icon

The dates are set in EmComponent::create() for date_create and in EmComponent::save() for date_update
The values are sets to datetime.datetime.utcnow() so we now that EVERY date in the db are in UTC, no matter django, database or even server configurations.
We will have to take care to convert dates from database to django timezone in dates fieldtypes.

Added a classmethod EmComponent::newUid() that determines the caller's class and return a newly registrated UID

SQL calls are in _populateDb , _saveDb and _createDb methods (exception for component::delete() )

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)