Rename tags for consistency with other KDE repos.

git-svn-id: https://svn.code.sf.net/p/rkward/code@5001 7936002b-cd1d-0410-9ce3-d7ebf93b5162
Also handle merging message catalogs with existing translations in the extraction script.

git-svn-id: https://svn.code.sf.net/p/rkward/code@5002 7936002b-cd1d-0410-9ce3-d7ebf93b5162