[paragui-users] changes to PG_Button

[Keith Swyer]

i think a few changes to the PG_Button class are in need. they are very
small and deal with the button being in toggle mode. in the eventEnter and
eventLeave and the eventButtonup there are a few changes to make the buttons
work a little nicer.

 eventMouseButtonUp .... last lines

if(!IsMouseInside()) {
  my_state = BTN_STATE_NORMAL;
  ReleaseCapture();
  Update();
  return false;
 } else {
**  if(!my_internaldata->togglemode)
   my_state = BTN_STATE_HIGH;
 }

eventMouseEnter
**if (!(my_internaldata->togglemode&&my_internaldata->isPressed))
   my_state = BTN_STATE_HIGH;

eventMouseLeave
if(my_state == BTN_STATE_HIGH) {
**  (my_internaldata->togglemode&&my_internaldata->isPressed)?my_state =
BTN_STATE_PRESSED:my_state = BTN_STATE_NORMAL;

 }