Finish Register class (issue #3)

This version introduces multiple enhancements:

added some reqired method to handle calling objects and singletons

Details of additions/deletions below:
--------------------------------------------------------------

Modified:   Base/Register.php
            -- Added --
                Exception usage
                $tracerDisabled
                $eventDisabled
                $_singletons
                initialize initialize Register object
                clearErrors
                hasErrors
                getErrors
                getSingleton
                destroy
                name2code
                _setObject
                callEvent
            -- Updated --
                $_classCounter is now static variable
                setObject renamed to getObject and finished logic
                getRegisteredObjects usage of $_singletons
                getClassCounter convert to static
                setClassCounter convert to static