(bug 49334) Create an 'arbcom' group on the Russian Wikipedia

Creating a new user group with the 'browsearchive', 'deletedhistory',
'deletedtext' and 'abusefilter-log-detail' user rights per community
request expressed in the bug.

Bug: 49334
Change-Id: Iacf89af36bf123aa01397e8f699f5cee1056d405