Commits
Merge pull request #419 in CASA/casa6 from CAS-13526 to master
* commit '99b83faabb8124f0b642f824bbf4784f0dcfdfbd': differing print statments still caused error. created a different write to std error function added alternate error printing when using python2 moved merged test to casatasks and removed old vishead test. Updated the unittestlist file and CMake file renamed test_vishead to test_req_task_vishead merged test_vishead and test_req_task_vishead