WLM 2013 survey

Long answer: The 2013 survey uses «title», «survey-mode-preparation», «survey-mode-closed» plus all the messages prefixed with «2013-». The messages beginning with «2012-» are not used by 2013 survey and don't need translation, but they are used by http://toolserver.org/~platonides/wlmsurvey/wlm2012.php and thus removing them would break that page (which IMHO should be kept as an archive). There are also some references in qqq that could break. If ‘disabling’ is different than ‘removing’ then sure, feel free to disable those but that's a new concept for me.