Re-written disclaimer

- The original disclaimer violates the end tag nesting rules
- There were two different disclaimers for both languages
Applied further changes to ZipWriter

Instead of throwing an exception, you better set the date to zero, so a
date prior 1980-01-01 00:00 UTC will also be possible.
Added support for directory date
Applied small optimization

To prevent redundancy
Fixed formatting
Fixed several issues
Fixed comments
Added support for Joomla

See
http://beta.woltlab.com/index.php/Thread/3347-PasswordUtil-Erg%C3%A4nzung-f%C3%BCr-Kunena-Joomla
Update AbstractUserNotificationEvent.class.php

Permissions and options for events should be evaluated by default (may be overwritten by derived classes)

Currently notification settings for conversations are displayed even if module is disabled (not to speak about problems with my own optional notifications)
Small style optimization
Merge branch 'master' of github.com:WoltLab/WCF
Fixes some label (group) management issues
Removes obsolete import
Adds default implementation of IApplication::__run()
Adds missing page titles in ACP
Fixed error message if updating package lists failed
Properly remove package archives upon success
Fixed word wrap issue
Merge branch 'master' of github.com:WoltLab/WCF
Fixed overflow issue in attachment list