githib pull request #232 - curses symset

This time I'm putting things in as-is before making a few tweaks.

The pull request was three or four separate changes.  I used the
patch instead so they've been collected into one commit.

src/drawing.c

@@ -543,6 +543,7 @@ boolean name_too;
     /* initialize restriction bits */
     symset[which_set].primary = 0;
     symset[which_set].rogue = 0;
+    symset[which_set].fallback = TRUE;
 
     if (name_too) {
         if (symset[which_set].name)

src/options.c

@@ -2315,6 +2315,7 @@ boolean tinitial, tfrom_file;
             } else {
                 if (!initial && Is_rogue_level(&u.uz))
                     assign_graphics(ROGUESET);
+                symset[ROGUESET].fallback = FALSE;
                 need_redraw = TRUE;
             }
         } else
@@ -2339,6 +2340,7 @@ boolean tinitial, tfrom_file;
                 return FALSE;
             } else {
                 switch_symbols(symset[PRIMARY].name != (char *) 0);
+                symset[PRIMARY].fallback = FALSE;
                 need_redraw = TRUE;
             }
         } else
@@ -6008,8 +6010,10 @@ int which_set;
 
     if (read_sym_file(which_set)) {
         switch_symbols(TRUE);
+        symset[which_set].fallback = FALSE;
     } else {
         clear_symsetentry(which_set, TRUE);
+        symset[which_set].fallback = TRUE;
         return 0;
     }
     return 1;