Turn on the pip cache directory

dstufft · dstufft · commit cca9e4b58d51 · 2015-02-06T09:41:53.000-05:00
diff --git a/.travis.yml b/.travis.yml
@@ -2,6 +2,9 @@ language: python
 
 sudo: false
 
+cache:
+  - pip
+
 env:
   - TOXENV=docs
 
