Api addition request Model.create( objectOrArr, cb )

Hey, i keep running into the same problem which takes me forever to find the reason for. What i do is i accidentally pass only one object (not an array with one object) into Model.create() ... the callback has no error but the results variable is empty.

I guess most of the cases people will want to create only one item, so i propose to allow for the API to be:

Model.create( objectOrArray, cb )
