Get rid of getattr in modules generated with thrift.load.

[abhinav]

This should be fairly trivial. We already iterate through all services and setattr them on the generated module. The same could be done for types, includes, and constants.

Worth noting that these attributes were renamed from foo to __foo__ in 1.0 and __includes__ is new in 1.0. So the code will have to use some hasattrs when doing this.