Patch by Don-Vip fix #8311: Should focus on the proper column when double-clicking to edit a key/value +
see #8024: focus on Value after Alt-E, focus on Key after Shift-Enter, recent tag Click or Shift-Click

git-svn-id: http://josm.openstreetmap.de/svn/trunk@5656 0c6e7542-c601-0410-84e7-c038aed88b3b