Updated landing page and other ideas to modify the site

[edwardchalstrey1]

• Landing page of this site should probably include simplified version of info from the docs landing page maybe highlighting 3 ways of using:
  • Command line tools, including Python API
  • AI tools (or say this is WIP)
  • GUI
• Install page should be removed from this site
• Make navbar disappear when you get further down
• Add navbar links to GH, PyPI, releases under an info dropdown
• Get started button should link to readthedocs
• Add photos to team page if possible
• Make software and methods sections larger
• Ensure site looks good on mobile
• Include some information on research domains and/or key projects that have used or are using Gambit
  • related to Collect information on Gambit userbase past and present alan-turing-institute/gambit_admin#5
  • I added a research page which can be updated

Remaining todos

• Merge main into branch
• Subtitle change: strategic -> strategic form
• Ensure methods section makes sense
• Update the "Active research" bit to be "Selected projects using Gambit" so it's more stale-proof
• Update the history diagram to reference "Automated analysis of strategic interactions" and differentiate "Early-2020s" and 2020s
• Add Stephen to people page and perhaps move Yongzhao to a past people section or remove
• Check again if we can host site on PR link

### Move to backlog issues

• Add user testimonials #15
• "Get involved" section #16