Adds NG states to php-formula

This rather big pull requests adds NG states to the php formula much in the same way we did with NGINX. It does require the helium release (or an updated pillar module) in order to take advantage of `salt.modules.pillar.get(merge=True)`.
This was a helpful neat little trick; order mattered in the ini files but lists would have ruined the slick merge pattern of the pillar/defaults. So, instead, we serialize as list of dicts.