6786: Invoke editor on double-click in backlinks gramplet

git-svn-id: svn+ssh://svn.code.sf.net/p/gramps/code/branches/maintenance/gramps40@22955 4ae1f11a-8b86-4847-b8af-ab372f36d1fd
6874: Use shorter names in add gramplet list.  Remove old attributes gramplet.

git-svn-id: svn+ssh://svn.code.sf.net/p/gramps/code/branches/maintenance/gramps40@22958 4ae1f11a-8b86-4847-b8af-ab372f36d1fd
flags HAS_CLIMERGE and HAS_EXPORTRAW to skip tests

Reapply from trunk my commit r22948

git-svn-id: svn+ssh://svn.code.sf.net/p/gramps/code/branches/maintenance/gramps40@22961 4ae1f11a-8b86-4847-b8af-ab372f36d1fd
6960: Error merging citations

Merge back to gramps40 my work on the bug fix.

git-svn-id: svn+ssh://svn.code.sf.net/p/gramps/code/branches/maintenance/gramps40@22962 4ae1f11a-8b86-4847-b8af-ab372f36d1fd
Finish merging bug# 6960 fix from trunk

I don't know why git diff didn't pick up citation.py :(

git-svn-id: svn+ssh://svn.code.sf.net/p/gramps/code/branches/maintenance/gramps40@22963 4ae1f11a-8b86-4847-b8af-ab372f36d1fd