add missing 'extend RailsAttrEnum' to example 'User' models. add some more examples. fix a typo.
Fixes a bug where many identifiers are passed

This commit fixes a bug where if you pass multiple identifiers,
and the first one is a hash to specify the value or label,
'rails_attr_enum' just assumed you were passing all your enum
configuration through that first hash.
bump to v0.0.3
Merge branch 'dev'