chore: fix travis yarn caching

Matt Lewis · Matt Lewis · commit a5b15a578109 · 2016-12-18T14:47:28.000Z
diff --git a/.travis.yml b/.travis.yml
@@ -8,6 +8,4 @@ script: npm test
 notifications:
   email: false
 
-cache:
-  directories:
-    - node_modules
+cache: yarn
