improvement of #723 which fixes the contenttype for text
Contacts: Some Exceptions weren't namspaced.
Merge branch 'master' into contacts_backends

Conflicts:
	contacts/lib/addressbook.php
	contacts/lib/vcard.php
Contacts: Moved structureContact etc to JSONSerializer class.
Contacts: Moved translated parameters to utility class.
Contacts: Remove obsolete methods.
Contacts: Cache queries in Database backend.
Contacts: Remove obsolete methods.
Contacts: Stripped out stale code.
Contacts: var 'url' => 'uri'.
Contacts: Move checksum check to Contact.
Updated 2012 => 2013