Start migrating return-value tests from run.py
Start migrating return-value tests from run.py

kejbaly2/invoke,tyewang/invoke,frol/invoke,singingwolfboy/invoke,frol/invoke,pyinvoke/invoke,mkusz/invoke,pyinvoke/invoke,kejbaly2/invoke,pfmoore/invoke,mattrobenolt/invoke,mkusz/invoke,mattrobenolt/invoke,pfmoore/invoke