New Course: Introduction to Kit and Gill

[L0STE]

@nickfrosty open to suggestion here! 👀

[nickfrosty]

for an introduction, we could create one that covers the core parts of using gill: connecting to an RPC, fetching accounts and data, decoding accounts, building basic transactions and instructions, signing them, and sending them

See the gill docs quick start that shows some of this: https://gill.site/docs#install-gill

and the recent helius blog post I wrote: https://www.helius.dev/blog/gill