Squashed commit of the following:

commit 28a74be0f614f0b1586916433f10bb5a80168d6e
Author: Marc Bonsels <marc.bonsels@otrs.com>
Date:   Fri May 31 09:48:11 2013 +0200

    Added edit button to activities and transitions.
Merge branch 'master' of git.otrs.com:otrs/otrs