Merge pull request #970 in CASA/casa from bugfix/CAS-12148 to master
* commit '147fc200dcb21d9d98fe6c598e5d7fbe56e2592d':
Corrected unit tests that make use of a restoring beam/common beam.
Added restoring beam tests to task_tclean.py.
Add a blank space, to commit, and trigger a re-build of tar balls !
CAS-12148 : Added verification tests
Multiply residual by ratio or beams