see #7846 - Large code refactorization in management of popup menus to simplify interactions with plugins (needed at least for imagery-xml-bounds and tag2link plugins)

git-svn-id: http://josm.openstreetmap.de/svn/trunk@5821 0c6e7542-c601-0410-84e7-c038aed88b3b
Merge branch 'master' into mirror