Finish jamboree updates

• New «Celebrating 20 Years of iGEM» box next to the top slideshow gallery.
• Villages Section: Pictures are linked — High School & Foundational Advance icons need to be updated — Modal popups for each village are designed.
• Pavilions & Booths Section: Pictures and Logos are linked
• Keynote Sessions Section: Design needs update to match Final Day Show Recap Videos Section
• Mobile design: The header section needs rework to make it fit in the top half of the screen.