Treat ‘encoding’ and ‘ticks’ as keywords

PHP allows the declaration of certain directives:

    http://php.net/declare

We currently highlight those directives in the warning font-face.
This patch presents a simple solution: treat the acceptable directives
as keywords.  This is not the most ideal implementation, but it is the
most simple so that we can fix the incorrect fontification we
currently have.
Update the Changelog for version 1.10
Update php-mode to version 1.10