Fixed bug in util.JSONEncoder for encoding Model objects.
Moved routing logic from WsgiDispatcher to WsgiRoute and added positional argument mapping support.
Added FieldPythonData field type.
Fixed bug when initializing a FieldData.
Fixed bugs for most field types when value is None.
Added ModelMapper map_from and map_to methods for serialization like behavior.
Sqlite: Added support for BLOBs for unknown type.
Fixed bug where FieldRefAny value would not be unpacked on retrieval.