More details about called objects (issue #14)

This version introduces multiple enhancements:

usage of ReflectionClass to return informations about singletons
also possibility to return called object by ReflectionClass instance

Details of additions/deletions below:
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Modified:   Base/Register.php
            -- Updated --
                getRegisteredObjects, added $singletonKey variable to return info about given singleton and return object information as ReflectionClass instance
                getObject can return instance of ReflectionClass