Bugreports keep coming in... including real bad one.

- Deformed mesh didnt give correct 'orco' anymore on render
- Mesh editmode, "Separate loose parts", crash on empty mesh (no verts)
- Global undo; buttons sending redraw events gave extra undo push called
  "Make single user or local". That latter was wrong event handling for
  REDRAW event, harmless, until now :)

First one is a real showstopper... bah!

source/blender/include/blendef.h

@@ -154,6 +154,10 @@
 
 /* do_global_buttons(event) */
 
+// (first event)
+#define B_LOCAL_ALONE	20
+
+
 #define B_ACTLOCAL		24	/* __NLA */
 #define	B_ACTALONE		25	/* __NLA */
 #define B_ARMLOCAL		26	/* __NLA */