Remove Chrome Web App links

https://chrome.google.com/webstore/detail/devdocs/mnfehgbmkapmjnhcnbodoamcioleeooe yields HTTP 404.

Fixes #1750.

README.md

@@ -147,7 +147,6 @@ Made something cool? Feel free to open a PR to add a new row to this table!
 
 | Project                                                                                                 | Description                                                            | Last commit                                                                                                                                                                |
 |---------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
-| [Chrome web app](https://chrome.google.com/webstore/detail/devdocs/mnfehgbmkapmjnhcnbodoamcioleeooe)    | Chrome Web App which adds a shortcut to DevDocs apps page.             | N/A                                                                                                                                                                        |
 | [Ubuntu Touch app](https://uappexplorer.com/app/devdocsunofficial.berkes)                               | Application for devices running Ubuntu Touch.                          | N/A                                                                                                                                                                        |
 | [Sublime Text plugin](https://sublime.wbond.net/packages/DevDocs)                                       | Sublime Text plugin to search DevDocs by selection or by input.        | [![Latest GitHub commit](https://img.shields.io/github/last-commit/vitorbritto/sublime-devdocs?logo=github&label)](https://github.com/vitorbritto/sublime-devdocs)         |
 | [Atom plugin](https://atom.io/packages/devdocs)                                                         | Atom plugin adding the `doc` command to search DevDocs.                | [![Latest GitHub commit](https://img.shields.io/github/last-commit/masnun/atom-devdocs?logo=github&label)](https://github.com/masnun/atom-devdocs)                         |

assets/javascripts/templates/pages/about_tmpl.coffee

@@ -30,7 +30,6 @@ app.templates.aboutPage = -> """
 
   <h2 class="_block-heading" id="plugins">Plugins and Extensions</h2>
   <ul>
-    <li><a href="https://chrome.google.com/webstore/detail/devdocs/mnfehgbmkapmjnhcnbodoamcioleeooe">Chrome web app</a>
     <li><a href="https://github.com/egoist/devdocs-app">Desktop app</a>
     <li><a href="https://sublime.wbond.net/packages/DevDocs">Sublime Text package</a>
     <li><a href="https://atom.io/packages/devdocs">Atom package</a>

assets/javascripts/templates/pages/root_tmpl.coffee.erb

@@ -36,7 +36,7 @@ app.templates.intro = """
       <li>The search supports fuzzy matching (e.g. "bgcp" brings up "background-clip").
       <li>To search a specific documentation, type its name (or an abbr.), then Tab.
       <li>You can search using your browser's address bar &mdash; <a href="/help#browser_search">learn how</a>.
-      <li>DevDocs works <a href="/offline">offline</a>, on mobile, and can be installed on <a href="https://chrome.google.com/webstore/detail/devdocs/mnfehgbmkapmjnhcnbodoamcioleeooe">Chrome</a>.
+      <li>DevDocs works <a href="/offline">offline</a>, on mobile, and can be installed as web app.
       <li>For the latest news, follow <a href="https://twitter.com/DevDocs">@DevDocs</a>.
       <li>DevDocs is free and <a href="https://github.com/freeCodeCamp/devdocs">open source</a>.
           <object data="https://img.shields.io/github/stars/freeCodeCamp/devdocs.svg?style=social" type="image/svg+xml" aria-hidden="true" height="20"></object>