Added GLK12232-25SM support with glk driver.

Fixed lots of small problems in various places.
Added new protocol commands screen_add/del_key so screens
   can request keystrokes when they are being displayed.
Lots of work on CPU GRAPH and BIG NUMBER CLOCK screens.
Fixed 'output' function in MtxOrb.c

server/screen.c

@@ -153,9 +153,6 @@ screen_remove (client * c, char *id)
 	// TODO:  Check for errors here?
 	LL_Remove (c->data->screenlist, (void *) s);
 
-	// ... and here?
-	screen_destroy (s);
-
 	// Now, remove it from the screenlist...
 	if (screenlist_remove_all (s) < 0) {
 		// Not a serious error..
@@ -163,5 +160,8 @@ screen_remove (client * c, char *id)
 		return 0;
 	}
 
+	// TODO:  Check for errors here too?
+	screen_destroy (s);
+
 	return 0;
 }