symbol preprocessing (trunk only)

Clean up the preprocessing associated with the
loadable symbol stuff.

Base it on new LOADSYMSETS, rather than on the
previously existing ASCIIGRAPH preprocessor define.

include/config.h

@@ -355,6 +355,8 @@ typedef unsigned char	uchar;
  * complexity of the game but also to the size of the load module.
  */
 
+/* display features */
+#define LOADSYMSETS	/* loadable symbol sets; only default symbols w/o this */
 /* dungeon features */
 #define SINKS		/* Kitchen sinks - Janet Walz */
 /* dungeon levels */