Fixed compile errors after API changes.

git-svn-id: http://svn.openstreetmap.org/applications/editors/josm/plugins@29869 b9d5c4c9-76e1-0310-9c85-f3177eceb1e4
Adapt to changes in 6115.

git-svn-id: http://svn.openstreetmap.org/applications/editors/josm/plugins@29870 b9d5c4c9-76e1-0310-9c85-f3177eceb1e4
Update icon (size).


git-svn-id: http://svn.openstreetmap.org/applications/editors/josm/plugins@29872 b9d5c4c9-76e1-0310-9c85-f3177eceb1e4
Fixed required JOSM version (6162 -> 6115)

git-svn-id: http://svn.openstreetmap.org/applications/editors/josm/plugins@29873 b9d5c4c9-76e1-0310-9c85-f3177eceb1e4