Pull request #605: CAS-13864: Remove non-production ready code from synthesis
Merge in CASA/casa6 from CAS-13864 to master
* commit 'a670eb78bbdbf07ff7b1812182c9e7ce0e9395a2':
Remove obsolete Pixon method based on IDL routines
Remove experimental files from production tree
Move back legacy files to casa5 directories