Mock-decorators

- Add coverage report

[](https://travis-ci.org/fhuertas/mock_decorators) [](https://coveralls.io/github/fhuertas/mock_decorators?branch=1.1.1)

New Mock. MockSysOutput catch the system output in a Stream
Fix documentation of FunctionMockCheckCall

- FunctionMockCheckCall now check 0 invocations
- Fix: FunctionMockCheckCall checks if the value to return is None and not a condition
- Fix: the checks in the FunctionMockCheckCall

- FunctionMockCheckCall checks if the value to return is None and not a condition

- The FunctionMockCheckCall now can return a value instead invoke the original function

- Added mock for check if a function is called
- FIX: make test-versions makes tests for python 2 and 3