Added wildcard support for ACL categories

Fixes #1142
Empty object id is now properly handled
Fixed loading of ACLs
Small style optimization
Merge branch 'master' of github.com:WoltLab/WCF
Fixes variable
Included image viewer on every page
Fixed user group cache
Small style optimization
Fixed broken link
Added minlength/maxlength
Adding regex flags

PREG_OFFSET_CAPTURE is a very important flag
Update textOptionType.tpl to validate minlength an maxlength
Merge pull request #1154 from PhrozenByte/enhancement/RegexFlags

Adding regex flags
Optimize updating user group options
Improve clearness in Regex
Properly save status code in HTTPRequest
Added method to get multilingualism status
Merge branch 'master' of github.com:WoltLab/WCF
Adding array comparison methods

Allows comparison of two arrays (just values, just keys or keys and values) while ignoring the item order. You can use callbacks, too.