Adjustments to securepoll and usergroups for voteWiki

* Enable SecurePoll namespace for voteWiki (supposed to happen last patch)
* Add new user right for those running current election allowing editinterface
* Allow permenant election committee and staff advisors add/remove electionadmin right

Bug: 72589
Change-Id: I3170248669533bc7d7e83d068cb56d8acef0da15