Added some tests  #384
Added some tests  #384

nicolascine/mongoengine,yarneo/mongoengine,larsbutler/mongoengine,gavincabbage/mongoengine,Multiposting/mongoengine,ms5/mongoengine,Davidrjx/mongoengine,jimmyshen/mongoengine,elephanter/mongoengine,cogniteev/mongoengine,cogniteev/mongoengine,prijindal/mongoengine,reallistic/mongoengine,eli-b/mongoengine,Davidrjx/mongoengine,aszwemin/mongoengine,RussellLuo/mongoengine,iandd0824/mongoengine,blaggacao/mongoengine,muhammad-ammar/mongoengine,hmarr/mongoengine,ConsumerPhysics/mongoengine,closeio/mongoengine,gmacon/mongoengine,starsirius/mongoengine,noirbizarre/mongoengine,conversocial/mongoengine,touilleMan/mongoengine,WingGao/mongoengine,colinhowe/mongoengine,sourcelair/mongoengine,DavidBord/mongoengine,MongoEngine/mongoengine,depop/mongoengine-stripped,khallaghi/mongoengine,nathanial/mongoengine,MRigal/mongoengine,ProgressivePlanning/mongoengine,losintikfos/mongoengine,Catstyle/mongoengine,MakerReduxCorp/mongoengine,9nix00/mongoengine,MakerReduxCorp/mongoengine