WIP Cartridge Refactor - Move PATH to /etc/openshift/env

* This allows cartridge path to be controlled by the PaaS operator
  * Cartridges may modify path based on their needs and accept responsibilty the needs of their packaged software.
* Update spec files
Merge pull request #2068 from jwhonce/wip/path

Merged by openshift-bot
Fixing F18 build of PHP v2 cartridge