Mark manager3 11 2013

Added some additional functionality to MarkManager.
-Added ability to select single or multiple marks in the listbox and adjust them using the +/- buttons or up/down arrows
-Added playback functionality with ability to view marks.
-Added playback speed change ability
-Moved Mark tapper ability to main screen - changed Mouse_Click to Mouse_Down to increase response time.
-Added necessary code in TimedSequenceEditorForm to get information to find if playback has reached the end of the sequence.  Assuming these changes are good it should resolve bug report #VIX-232