Fix #1627: Category selection dropdowns in views are missing
Fix #1630: Clean IP Addresses SQL error
Fix #1634: Duplicate language string in com_kunena.sys.ini
Fix #1618: Upgrade from 1.6.4 fails (after JUpgrade)
Merge pull request #1635 from mahagr/master

Fix #1627, #1630, #1634, #1618