Some fixes for PHP deployment and DB handling:

* Skip non-php apps when installing the PHP db drivers
* Fallback to MySQL driver
* Handle apps with no database config
Fix RAID-related cookbook tests.
Reboot after update if kernel has changed and reboot allowed.
Set Ruby 2.0.0 patch level depending on OS version.
Merge branch 'master-chef-11.4' into mainline-chef-11.4