[josm_plugins] see #josm8582 - Use Main.removeLayer() everywhere

git-svn-id: http://svn.openstreetmap.org/applications/editors/josm/plugins@29525 b9d5c4c9-76e1-0310-9c85-f3177eceb1e4
[josm_cadastre] update build.xml

git-svn-id: http://svn.openstreetmap.org/applications/editors/josm/plugins@29526 b9d5c4c9-76e1-0310-9c85-f3177eceb1e4