Merge pull request #2459 from alex/pypy-4

pypy 4.0.0
diff --git a/.travis/install.sh b/.travis/install.sh
index 114c7de..21e4152 100755
--- a/.travis/install.sh
+++ b/.travis/install.sh
@@ -60,8 +60,8 @@
         PYENV_ROOT="$HOME/.pyenv"
         PATH="$PYENV_ROOT/bin:$PATH"
         eval "$(pyenv init -)"
-        pyenv install pypy-c-jit-latest
-        pyenv global pypy-c-jit-latest
+        pyenv install pypy-4.0.0
+        pyenv global pypy-4.0.0
     fi
     pip install virtualenv
 fi