use pypy 2.5 on our os x builders
diff --git a/.travis/install.sh b/.travis/install.sh
index 418aeed..26a82c4 100755
--- a/.travis/install.sh
+++ b/.travis/install.sh
@@ -46,8 +46,8 @@
             ;;
         pypy)
             brew upgrade pyenv
-            pyenv install pypy-2.4.0
-            pyenv global pypy-2.4.0
+            pyenv install pypy-2.5.0
+            pyenv global pypy-2.5.0
             ;;
         pypy3)
             brew upgrade pyenv