Removed font declaration from drop downs

Disabled ipv6 mirror rewriting in this release. This feature is still under development and will get added in 3.0.6

- Adde some missing strings to translations in faq module.

- Added missing validator for xfer field in dns zone fom

Fixed:  FS#2066 - Check if problems can occur ins ervices when the default prefix is manually changed
 - Notes:
   once the entry was created or modified after applying this update the current prefix is stored with the entry and kept even if the global prefix changes

- Added check that aps plugin installs package only once on a mirrored system
- Added "IPCCommTimeout  7200" in ispconfig apache vhost.

- Bugfix: sys.ini and server.ini: if checkbox is not checked, write default value from tform file into database.