Chrome Extension Tutorial:
    https://thoughtbot.com/blog/how-to-make-a-chrome-extension


How to Load Exetension:
    To load your extension in Chrome, open up chrome://extensions/ in your browser
    and click “Developer mode” in the top right.
    Now click “Load unpacked extension…” and select the extension’s directory.
    You should now see your extension in the list.

    When you change or add code in your extension, just come back to this page and reload the page.
    Chrome will reload your extension.