For client account / profile updates

Add client registration methods and login required checkbox

Conflicts:
	WHATSNEW.md

Conflicts:
	include/class.mailparse.php

Conflicts:
	include/staff/templates/user-lookup.tmpl.php

lint: Fail on js syntax errors

Reviewed-By: Peter Rotich <peter@osticket.com>

mysqli: Allow for persistent database spec

Reviewed-By: Peter Rotich <peter@osticket.com>

Allow disabling the collaborator features

Reviewed-By: Peter Rotich <peter@osticket.com>

  * Administrator can disable the new activity alert
  * Administrator can disable automatic collaborators from email headers

Use `p:` in the database hostname specification, so `p:localhost` for
instance. This will help with SSL and remote database users.

References:
http://www.php.net/manual/en/mysqli.persistconns.php