(bug 54922) Add an accountcreator user group on svwiki

Adding an 'accountcreator' user group on the Swedish Wikipedia
with the 'noratelimit' user right. Per community consensus,
local bureaucrats will be able to add and remove users from
this group; see bug for URL with on-wiki agreement.

Bug: 54922
Change-Id: Ibcb0d71a2a55262da6881f93d9037a36cb170c2b