Revert "Responsibility for loading config files moved from ContainerFactory to Compiler (BC break)"

This reverts commit 5b7f9b9098d7c564905b1a602d1d68eaafa3eff9.
ContainerFactory::$configFiles can contain arrays with configuration [Closes #26]
ContainerBuilder: removed needless checking of service's type
added ContainerCache: humble replacement for ContainerFactory