0. bump version 1.81 20130526
1. new: poll results are by default _not_ shown when the user has not voted
2. a new optional (per-poll) tag parameter "show-results-before-voting" is introduced
<poll show-results-before-voting>
<poll show-results-before-voting=1>
3. introduction of new group permissions:
* ajaxpoll-viewresults
* ajaxpoll-viewresults-before-voting
4. schema change
this version requires a database update ( php maintenance/update.php )
updater included
Change-Id: Iae1f3f2806afecbca3e3c41460dbbf20fc557525