[+FEATURE] FLOW3 (Cache): Implemented a PHP Cache Frontend which allows for effective caching of PHP code which is included with require_once() instead of runtime parsing with eval(). This significantly improves speed when used in combination with an opcode cache such as APC. Currently only the FileBackend supports PHP code caching. Resolves #6137
[+FEATURE] FLOW3 (AOP): The AOP Framework now uses the new PHP cache frontend for storing AOP proxy classes. Speeds up the initial startup of FLOW3 enormously. Relates to #6137
[~TASK] FLOW3: Removed all dependencies from the PHP6 package because the unicode support we were using didn't really make sense in the respective situations.
[+BUGFIX] FLOW3 (Utility): Fixed a bug in Files::emptyDirectoryRecursively() which wrongly recognized certain files as directories due to incorrect usage of the directory iterator.