Monitor playground.wordpress.net

[adamziel]

Let's setup a monitoring service to ensure playground.wordpress.net keeps rendering correctly. This is to avoid issues such as #174

Here's a few services that have been recommended to me:

• https://downtimemonkey.com/index.php
• https://uptimerobot.com/integrations/
• https://visualping.io/

Ideally it would request a post editor, wait until it's rendered, and if the visual differs from the last one it would open a new GitHub issue with both screenshots, a timestamp, maybe an output from the dev tools.