implemented goal and cancel callbacks for handling pickup and place client requests.  The run method no longer loops through a sequence of predefined pick and place goals.  That functionality has been move to another test class
added node 'move_pick_place_test' that implements a simple test class to demonstrate the pick and place functionality.  the CMakeList.txt and mtconnect_pick_place_test.launch files have been modified to reflect this change
committing this file just becaused it was incorrectly listed under the not staged area
modified the node name in order to provide a more correct description