Update Travis CI Node versions in User Guide (facebook#2454)

ryansully · romaindso · commit 4885c5d9f7aa · 2017-07-10T15:27:07.000+02:00
Removed Node v4 (CRA only supports Node &gt;= 6)
diff --git a/packages/react-scripts/template/README.md b/packages/react-scripts/template/README.md
@@ -1244,7 +1244,6 @@ Popular CI servers already set the environment variable `CI` by default but you
 ```
 language: node_js
 node_js:
-  - 4
   - 6
 cache:
   directories:
