DDC-3120 - adding instantiator dependency
DDC-3120 - add failing test for un-serialization of an internal PHP class
DDC-3120 - add failing test for un-serialization of an internal PHP class from cached metadata instance
DDC-3120 - need to wakeup reflection BEFORE using any `ClassMetadata` API
DDC-3120 - using `Doctrine\Instantiator` when building new instances
DDC-3120 - requiring `doctrine\instantiator:~1.0.1` as of doctrine/instantiator#4
Merge pull request #1109 from doctrine/hotfix/DDC-3120-php-5.6-RC3-compat

DDC-3120 - PHP 5.6-RC3 compatibility