docs(readme): update

Author: akameco

readme.md

@@ -10,6 +10,8 @@ This package will generate json or yaml files from a glob. It will generate one
 
 ## Install
 
+Babel 7
+
 ```
 $ npm install --save-dev extract-react-intl-messages
 ```
@@ -20,7 +22,6 @@ Babel 6
 $ npm install --save-dev extract-react-intl-messages@0.11.2
 ```
 
-
 ## Usage
 
 app/components/App/messages.js