fixed bug that incorrectly set the resource as materialized - dict.keys() is no longer a list in py3
latest httpretty breaks tests for py32 and py33 - again
fixed bug in tests - py3 doesn't rely on __cmp__ so it can't sort a list with dicts, integers and other lists automatically
moved custom_data import with other resource imports
ensure fetching of data if it isn't already fetched and override user set properties
just rely on _set_properties to do the right thing and set the materialized flag correctly
support for group custom_data added
uncommented tests marked FIXME since this works now, some pep8 fixes
deleting non materialized property causes an error but we should try to delete it on the server anyway
more tests for customData
__init__ - customData