Remove redefinitions of validators
Merge branch 'develop' of https://github.com/CenterForOpenScience/modular-odm into remove-redefinitions
Merge branch 'remove-redefinitions' of https://github.com/sloria/modular-odm into develop
Allow Mongo backend to take multiple queries on a single field

E.g. Q(‘foo’, ‘in’, [‘bar’]) & (Q(‘foo’, ‘nin’, [‘baz’])
Merge branch 'develop' of https://github.com/CenterForOpenScience/modular-odm into redis
Move some redisstorage tests to multidatabase query tests