this should fix some errors when registering models
fix for test 847

this test used to work because lib/models.js MODELS hash was populated
in the wrong way. we can't use patio.syncModels() to sync two different
models generated from the same table, because the second one will
overwrite the first inside MODELS
fix for test 850 - allow again passing a dataset to getModel()
Merge pull request #120 from cvlmtg/master

this should fix some errors when registering models