added functions to create global waypoinst, modifying the WaypointList class, MapWidget and MainWindows.

add the functionality to erase the list of Waypoint widget (WaypointView) from the button of the WaypointList widget

Changed NUM_OUTPUT_SIGNALS to an const unsigned short from a #define and moved its definition into OpalRT.h from OpalLink.h so that the configuration would all be in one place.

add widget WaypointView to widget WaypointList when create a waypoint with mouse over the map

OpalLink should now be able to be disconnected.  I also added a test to see if params had already been allocated before calling new in OpalLink::connect()