[BUGFIX] Clear PHP Opcode Caches in Caching, PackageManager and ConfigurationManager
This solves a lot of bugs when people use a wrongly configured
opcode cache (e.g. part of Bitnami MAMP stack).
Check the ticket for further background and how I could reproduce
the error on Bitnami MAMP stack.
Thanks to the TYPO3 CMS project for inspiration on the solution!
Releases: 3.0, master