-Fixed FS#2672 - Rename website - APS instance domain must be renamed as well.

- App Installer: make sure that package URLs get inserted in aps_packages table even when process of updating the packagelist is aborted or reloaded.
- Added an explanation page before package lists are updated.

- Merged language files.

- Extended the tform ISIP check and added the options 'allowempty' and 'separator'

- Bugfix: when you delete a client with a web site, website symlinks have to be deleted from the client directory before the client directory is deleted (because otherwise the client directory cannot be deleted).

- Added mousedown event to readonly tab (web domain and web vhostsubdomain forms) so that select boxes do not expand (Chrome, IE, Safari).

- Changed regex for redirect path (Web sites, subdomains, vhost subdomains, alias domains) and web folder (vhost subdomains) so that ".." is not allowed (in order to prevent path traversals).
- nginx: don't allow folders for proxy redirects (subdomains and alias domains); URL is required.
- nginx: modified rewriting.

 - included a maximum loop count of 10 on connection errors
 - added check of mysqli ping() result

 - on new vhost subdomain the php modes were not correctly displayed (nginx)
 - on vhost subdomains and domains the default php mode stated "fastcgi" even if it was not available

 - passwords are now enrypted already in tform (and remoting) and not stored in datalog clear text
 - clientdb plugin no longer encrypts password itself but receives crypted password

Removed font declaration from drop downs