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/widget.h

@@ -26,11 +26,15 @@ typedef struct widget {
 #define WID_SCROLLER 6
 #define WID_FRAME 7
 #define WID_NUM 8
+#define WID_KEYS 9
 
 #define WID_MAX_DIR 4
 
 extern char *types[];
 
+// RESERVED widget ID for keys active on a screen
+#define KEYS_WIDGETID "screenkeys"
+
 widget *widget_create ();
 int widget_destroy (widget * w);