Use pypy 1.6 instead of 1.5

Makefile

@@ -1,7 +1,7 @@
 
 go:
 	./this-pylint bloom_filter_mod.py test-bloom-filter
-	/usr/local/pypy-1.5/bin/pypy ./test-bloom-filter
+	/usr/local/pypy-1.6/bin/pypy ./test-bloom-filter
 	/usr/local/cpython-2.5/bin/python ./test-bloom-filter
 	/usr/local/cpython-2.7/bin/python ./test-bloom-filter
 	/usr/local/cpython-3.0/bin/python ./test-bloom-filter