Add highlighted project to homepage

[fallow64]

Resolves #415

Creates the following section on the homepage:

Projects rotate on a weekly basis based on the ROTATING_PROJECTS variable in assets/js/homepage-v1.js.

A few notes:

• Feel free to move around, should just be moving the div.
• The data loading takes ~1s, so somewhere a bit further down would prevent the user seeing it update.
• I added 3 rotating projects, but I'm not too sure what type of projects would be good to spotlight. Feel free to add/remove some :)
• If a user has slow data / JavaScript disabled, we can update index.html statically, although the projects wouldn't rotate and it would require manual updating.