fix #8642 - Fix NPE when deleting osm data layer with active validator layer

git-svn-id: http://josm.openstreetmap.de/svn/trunk@5907 0c6e7542-c601-0410-84e7-c038aed88b3b
fix #8641 - Do not raise warning for address nodes with no addr:street in interpolation way

git-svn-id: http://josm.openstreetmap.de/svn/trunk@5908 0c6e7542-c601-0410-84e7-c038aed88b3b
fix all remaining javadoc warnings

git-svn-id: http://josm.openstreetmap.de/svn/trunk@5909 0c6e7542-c601-0410-84e7-c038aed88b3b