global option to enable pagespeed with nginx - allows to enable pagespeed even if no webserver-config is selected

- cleaned up some javascript

- http://en.wikipedia.org/wiki/SPDY

- Added HHVM to "Default PHP Handler" field (server configuration).
- Fixed "Unable to load the server configuration from database." error when running server.sh.
- Fixed Javascript (accordions weren't working anymore, directive snippets and other placeholders couldn't be added anymore).

-Added a new option "Network Filesystem" under System > Server config > Web to toggle on / off the _netdev option for the bind mounts in /etc/fstab

 - added configuration options to server config (web tab, php section)
 - do not update custom php.inis if md5sum file does not exist

Fixed: password match function blocked tabs incorrectly
Fixed: set focus on username input field threw an error if this field did not exist on a page

Moved old default theme to themes/default-304

- Added overtraffic notifications to traffic quota system (part of FS#2059 - Extend Traffic quota system)

This option can be enabled under System > Server config and is named "Web folder protection".