Updating to 6.4

README.md

@@ -73,7 +73,7 @@ Here are some common mistakes people make, check these before filing an issue:
 - `ENOENT: no such file or directory, open '.env'`. You forgot to make a *.env* file. See step 3.
 - `EADDRINUSE :::3000`. You already have another application using port 3000. Either end it, or change your port to something else in the *.env* file to resolve the conflict e.g. `3001`
 - `Error: Request failed with status code 403`. You didn't create an Imgur API key, or didn't paste it into your *.env* file. See pre-installation step 2.
-- Ensure you have a version of Node >= 4
+- Ensure you have a version of Node >= 6.4
 
 ```
 node -v