fix gold pieces gls entry

glossary.tex

@@ -868,7 +868,7 @@ Set the darker die to `\dicef{6}' and roll the other.  If this roll fails, it fa
   category={rules},
   prefix={a\space},
   parent={coin},
-]{gp}{gp}{Gold Piece}
+]{gp}{gp}{gold piece}
 
 
 % Magic