Feature Request: supress screen timeout when using midi

[FredFoo]

When using a midi keyboard the screen turns off after a while. So you have to tap it regulary :) Maybe only my problem? I have this on two devices.

[code-monet]

Haven't tested it out, but I believe you :)

Here's the first link I found on how to do this. A couple of notes for whoever works on it (might be me, in a few weeks):

• Ensure the method chosen works for the web app as well as when packaged via Cordova.
• See if the recommended way has changed since this StackOverflow post.