Merge pull request #1357 from Axelrod-Python/fix-dbs-documentation

Fix name in documentation of dbs strategy.

Author: meatballs

axelrod/strategies/dbs.py

@@ -17,7 +17,7 @@ class DBS(Player):
 
     Names
 
-    - Desired Belief Strategy: [Au2006]_
+    - Derived Belief Strategy: [Au2006]_
     """
 
     # These are various properties for the strategy