fix #josm8635 - NPE in measurement plugin

git-svn-id: http://svn.openstreetmap.org/applications/editors/josm/plugins@29545 b9d5c4c9-76e1-0310-9c85-f3177eceb1e4
i18n fixes

git-svn-id: http://svn.openstreetmap.org/applications/editors/josm/plugins@29547 b9d5c4c9-76e1-0310-9c85-f3177eceb1e4
[josm_reverter] fix #josm8646 + code cleanup/update

git-svn-id: http://svn.openstreetmap.org/applications/editors/josm/plugins@29548 b9d5c4c9-76e1-0310-9c85-f3177eceb1e4
[josm_reverter] remove unused code

git-svn-id: http://svn.openstreetmap.org/applications/editors/josm/plugins@29550 b9d5c4c9-76e1-0310-9c85-f3177eceb1e4
[josm_reverter] fix #josm8040 - handling of redacted versions

git-svn-id: http://svn.openstreetmap.org/applications/editors/josm/plugins@29551 b9d5c4c9-76e1-0310-9c85-f3177eceb1e4