Homepage tweaks

[jacobgkau]

This makes a few homepage tweaks requested by @Socialhappiness.

• Renames the top-left section Support Articles to Support Documentation; adds the hardware guides article & removes the Learn section link from it.
  • Brought in a new screwdriver icon from the existing icon font for the new Guides link.
• Removes the Getting Help section, moving the two software troubleshooting articles into the software troubleshooting section and moving the website infrastructure article into the returns & repairs section.
  • Emma just requested the website infra article to be moved "somewhere nestled away." I think the returns & repairs section makes more sense than one of the troubleshooting sections because the article exists for infrastructural reasons, and it does talk about the returns & repairs process in addition to its basic troubleshooting triage info. As a reminder, this article's mainly intended as a redirect for older ticket URLs (we'd hide it from the index page altogether if it didn't break the redirect).

[jacobgkau]

Went ahead and removed the graduation cap icon from the repo for now since it's no longer used anywhere (any Font Awesome icons we want to use, including that one, can be added again when they're used).

[thomas-zimmerman]

Nice work getting that updated. Looks correct in npm live web view.