Group-Office 4.0 stable released!

After long series of beta testing it's finally complete!

The new features are:
- Search through the contents of files
- CardDAV support
- File locking in the files module
- Document workflow module
- Users are stored in the addressbook too.
- Ticket groups for better permission management.
- Better file upload component
- gnupg support dropped. smime still supported.
- Project tasks have a relation now and have a percentage complete field
- Photo support in sync.
- Sync multiple calendars
- Billing module can create MS word and open-office invoices, quotes and orders.
- Billing module can handle purchase orders and stock.

- New scanbox module to handle scanned documents in Group-Office

It's important to know that:
- the CMS module is no longer supported.
- We've dropped the Wordpress, PHPBB and formprocessor module.
- Vacation auto response is now handled by the sieve module. You need to install
    the module and make sure that your IMAP server supports the sieve and managesieve protocol.
    WARNING: Upgrading removes all active vacation auto replies
- SyncML datastores have been changed to: card, event and task