Add whatis_moveskip option to change fast-moving cursor

Previously the "fast-moving" when getting a target location
was always by 8 units. If this option is on, fast-moving
will instead skip the same map glyphs. This should be much more
useful for blind players.

src/cmd.c

@@ -3749,6 +3749,7 @@ struct {
     { NHKF_GETPOS_INTERESTING_PREV, 'A', "getpos.all.prev" },
     { NHKF_GETPOS_HELP,      '?', "getpos.help" },
     { NHKF_GETPOS_LIMITVIEW, '"', "getpos.filter" },
+    { NHKF_GETPOS_MOVESKIP,  '*', "getpos.moveskip" },
     { NHKF_GETPOS_MENU,      '!', "getpos.menu" }
 };