Merged IssuesController #edit and #update into a single actions.

Users with 'edit issues' permission can now update any property including custom fields when adding a note or changing the status (#519, #581, #587).

git-svn-id: http://redmine.rubyforge.org/svn/trunk@1129 e93f8b46-1217-0410-a6f0-8f06a7374b81