Sync README

Author: tony

README.rst

@@ -20,17 +20,20 @@ Usage
 
    npm run start  # launch + hot reloading + watch file changes http://localhost:3099
 
+
    npm run build  # build to dist/
 
 Environmental variables
 """""""""""""""""""""""
 
 `Webpack's environmental variables`_ can be passed (``--env``):
 
-``npm run start -- --env.devServerPort 3082``
+``npm run start -- --env.devServerPort 3082``, build + watch at http://localhost:3082
 
 ``npm run start -- --env.production``
 
+``npm run start -- --open``  Launch browser + build + watch files, http://localhost:3099
+
 .. _Webpack's environmental variables: https://webpack.js.org/guides/environment-variables/
 
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