message: Updated build instructions to include building webdriver.
diff: @@ -37,6 +37,7 @@ We are using [SideeX](http://sideex.org/) as a start point. The SideeX team was
  ```yarn``` or if using Node 10 ```yarn --ignore-engines```
  - Build the extension
  ```yarn build``` and then
  +```yarn build:webdriver``` and then
  ```yarn build:ext:prod``` or ```yarn build:ext``` for faster development build (also includes beta features)
  - Install as developer on [Google Chrome](https://developer.chrome.com/extensions/getstarted#unpacked) or [Firefox](https://developer.mozilla.org/en-US/Add-ons/WebExtensions/Temporary_Installation_in_Firefox)
  