Pull request #710: CAS-12599 new reqs for ia.restoringbeam implemented
Merge in CASA/casa6 from CAS-12599 to master
* commit '69eeccb9bf592927e42ff7423141330965e5c886':
Move run_shell_command to subprocess
Add --no-edit flag to git merge option to accept the auto-generated messag
Update to verbosity in git status for runtest merge test
Fix from CAS-14129 added to this branch for testing
fix exception message typo
updated test_immath for location of messages in output
added hopefully useful log messages
bug fix, fix some tests
Modified for new user-based rules
update setrestoringbeam() docs CAS-12599 add warning messages for special case of existing beam and specified major and/or minor axis having length 0
