tweak/sponsor logos displayed on welcome page

[cnandes]

Sponsor logos added to welcome/home page and link through to corresponding show pages. Makes sponsor information visible without the need to click through to "/sponsorship" page.

[Cueball]

Wow; I'm a bit stunned because I didn't expect this right now - and legit almost exactly what I'd pictured. Kudos 🙌

Two tweaks I'd suggest:

• Make the Up logo a tad larger? I know I spent quite a bit of time (back in January?) trying to balance their odd logo shape to not make it appear smaller than other logos.
  • If it's troublesome, leave it.
• For the first four (our "Major Sponsors", AssemblyFour through Buildkite) - can we make those logos larger/more prominent?
  • Again - IIRC? there's some janky layout code for the sponsor logos that means all the logos need to be the same size (or that might be the conf website, IDK?).

So if it's more than a few minutes work, leave it be and we can revisit the logo size issue in the future - not obligated to have logos on the RubyAU home page at all, so there's that 🙃. Otherwise, that's great work!

[leesheppard]

@cnandes can you share a screenshot of the mobile view of this layout?

[cnandes]

I've just pushed additional changes to better centre the logos for mobile and enlarge the up logo, but alas I will need to better look into those build failures at another time 🦇