Model._fields now tracks fields
Model setattr now uses _fields
Model getattribute now uses _fields
Merge pull request #1 from Widdershin/local-fields

Local fields
Super dirty implementation of write safe instances, and model.get_instances(). model.commit() must be used to save writes now
Removed some debug messages
Merge pull request #2 from Widdershin/model-instances

Model instances
Merge branch 'master' into mockdb

Conflicts:
	fuckitdb/fuckit.py
	tests/test_model.py