Change Future API to expose result(), cancel() and cancelled()
Merge branch 'master' into FutureResponse_v2

Conflicts:
	swaggerpy/response.py
	swaggerpy_test/resource_model_test.py
	swaggerpy_test/resource_operation_test.py
	swaggerpy_test/resource_response_test.py
Merge branch 'FutureResponse_v2'