Resolves #463, #801

Changes:

• Add descriptions for Agent Arena and RAFT
• Add more descriptions on BFCL (V1, V2, V3)
• Add links / icons
• Address Revamp repo folder structure - place /eval, and /inference under /gorilla folder #801
  • Double check the new folder structure doesn't break the existing colab notebooks (note: I've checked the links within the repo are consistent, but haven't check external links).
• Get Started section (very outdated).

• Restructure README formatting into appropriate sections.
  • Better starter examples, and README flow
  • High-Level summary in the beginning, ref: multiple reference fastchat https://github.com/lm-sys/FastChat?tab=readme-ov-file#fastchat
• Polish wordings on Gorilla Openfunctions V1, V2 releases
• Update news section
• Update repo structure explanation in README