Reduce drop frequency for town books as monster drops
(cherry picked from commit 2fe64775ed7ae0a40358e1475f31719756e8ba0c)
Drop object frequencies for all spell books
(cherry picked from commit a310ea72615587ee0fd4c983ef8522133f1a289c)
Merge pull request #216 from fizzix/fizzix_merge

Reduce book frequencies