Add tests for joins
Add tests for joins

adammcarth/rethinkdbdash,andrerpena/rethinkdbdash,JohnyDays/rethinkdbdash,marshall007/rethinkdbdash,dmitrig01/rethinkdbfake,abhishekgahlot/rethinkdbdash,beni55/rethinkdbdash,neumino/rethinkdbdash,kulbirsaini/rethinkdbdash,tswayne/rethinkdbdash,mbroadst/rethunk,mbroadst/rethinkdbdash