Now _fields and table MUST be class attribute.
Its important to note that _fields now consist in a list of (name, ftype) tuples and that ftype is a EmFieldType class and NOT an EmFieldType instance
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.
