Initial commit/skeleton for Flavor model
Flavor resource: adds capacities to serialization and also get_one method
Flavor resource: adds delete and fixes links (self) in serialization
Merge remote-tracking branch 'marios/flavors'

Conflicts:
	tuskar/api/controllers/v1.py
	tuskar/db/sqlalchemy/api.py
	tuskar/db/sqlalchemy/models.py