rename diggers gDiggers

The mim book already uses 'diggers' for a political movement.

glossary.tex

@@ -1259,7 +1259,7 @@ Fewer monsters wander through them, because fewer plants grow there},
   About half of these new recruits will survive and gain the next rank},
 }
 
-\longnewglossaryentry{digger}{
+\longnewglossaryentry{gDigger}{
   name={Diggers},
   text={digger},
   prefix={a\space},