Fix Model Meta Class __new__

[sethdenner]

• Model meta class was using the passed in model instead of looking up the model registered with Django. I don't know what voodoo happens here but the passed in model does not have all the information required to properly render out the schema.

[coveralls]

Coverage remained the same at 63.708% when pulling c08500b3f45da54569b8b5e68ea69b48e5a150d3 on sethdenner:fix-model-creation into 9fceeea64745aa7031b8fc742ca8947d6e0a1da2 on Knotis:master.