Merge in CASA/casa6 from CAS-14435 to master
* commit 'e93b7529ba195e886e8193e4a60804a99778c099':
revert gitmodules
MSMetaData update
looks like i can't get hyperlinks to work in xml docs
try using xml entities for "special" characters
more updated docs
updated docs in msmetadata.xml
CAS-14435 test to verify fix for fdm misidentification for heavy online channnel avg
update .gitmodues for testing, new dmehring casacore pointer
revert to original to see if bamboo will build
change casacore pointer to dmehring ticket branch