mim: better _project
mim text search: better text indexes gathering
schema validation: convert datetime.date to datetime.datetime
added dummy $search operator in mim
if _id in collection._data.keys(): probably wants to be replaced with if _id in collection._data
That's not strictly a bug as it's the currently documented behaviour ( http://ming.readthedocs.org/en/latest/polymorphism.html#querying-polymorphic-entities...