Tools: Run PHP code sniffer in the make phplint command

Standardise on a set of PHP code conventions
Provide instructions for setup.

Change-Id: I364b2c2899598f455a548b48725919ad56de09f6
Hygiene: Fix remaining php code sniffer errors

Rejoice in no errors

Change-Id: I6e65d3abad11a24dbba0c0696d773bfd931aaa85