Add more visible link(s) to source code when viewing on small screens

[siccovansas]

On large screens there is a link to the repo in the header. This link is not visible on small screens. I was looking for the repo link and only found it on the install page. Maybe create a hamburger menu on small screens. Or add it to the footer.

[mholt]

Yeah, I had to quickly fix the nav this morning to make it look good on small screens. It should definitely be a hamburger menu or something.

[itsausting]

I ran into the same problem this morning while trying to find the repo on my phone!

[mholt]

I hear ya. Would anyone like to submit a PR to make this better? (Ideally no JS for just a menu.)