Merge pull request #24 in CASA/casaviewer from CAS-13252 to master
* commit '8429ab68c091b959883f3ff8bcaf2d165b428b6c':
update casaviewer to updated casa6 branch (CAS-13252)
Revert "Revert "CAS-13252 update to pull the latest version of casa6 source, don't include files that were removed in casacore (Mutex.cc)"" CAS-13252 update to pull the latest version of casa6 source CAS-13252 update to pull the latest version of casa6 source
Revert "Revert "CAS-13252 update to pull the latest version of casa6 source, don't include files that were removed in casacore (Mutex.cc)""
This reverts commit a9840944cd3a2b32ebc14dfd4b34a866280ca974, which was made to undo the changes that got pushed directly to master. We do still want the changes, just not directly in the master branch.
