Add partial keyword to generated types.
Fix generated factory interface filename when defining a specific type is passed to GenerateT4FactoryWithContractAttribute.
Merge remote-tracking branch 'origin/master'

Conflicts:
	T4Factories.Testbed/Contracts/IFooFactory.Generated.cs
	T4Factories.Testbed/Models/FooFactory.Generated.cs
Make file name generation play better with generics.