fix: address Awesome.re comments

[pgray-hiro]

This PR fixes remaining issues identified during the Awesome.re PR process. You can review comments here. The primary suggestions were:

• Change title from Stacks Chain to Stacks for consistency with the project. He is not concerned with the naming collision between this and the Awesome Stacks related to tech stacks.
• Consistency and correctness in naming - STX, Bitcoin, Lightning Network, TypeScript, JavaScript were all identified as either not consistent or not correctly formed.
• Update the introduction text to include a link to the Stacks website (I put it to the What is Stacks page, because if we link to the root of the site we get an awesome-lint error for having the same link twice.
• Update the introduction text to include more context on what Stacks is and why it's cool.

In addition to these suggestions, I modified 2 of our section headings. I've been reviewing other Awesome lists and it isn't common to see the word "Awesome" in the section headings - just the title of the list. While this change wasn't specifically requested, I think it's an improvement and makes our list more similar to other lists that have already been included.