Break out community section on website

[starkos]

What does this PR do?

Moves community-related website content out of the 5.x specific docs and into its own top-level area.

How does this PR change Premake's behavior?

No changes to Premake code, just the website.

Anything else we should know?

Addresses a portion of the work required to resolve #1547.

Did you check all the boxes?

• Focus on a single fix or feature; remove any unrelated formatting or code changes
• Add unit tests showing fix or feature works; all tests pass
• Mention any related issues (put closes #XXXX in comment to auto-close issue when PR is merged)
• Follow our coding conventions
• Minimize the number of commits

You can now support Premake on our OpenCollective. Your contributions help us spend more time responding to requests like these!

[KyrietS]

Good idea with making a new folder for community stuff 👍

While you are moving showcase I checked the links there so you can update the list according to my suggestions. In any case I consider this PR approved 🥇

By the way, I don't know why CI tests for binary are yellow. They should be skipped (because of paths-ignore) but they are marked as "expected"/"required" 🤔 Master branch is protected and maybe there is some kind of setting that makes those tests "required"?

[KyrietS]

Ok, I got it. In the repo's settings there is a rule for master branch that those tests are necessary to merge. In this situation I suggest removing:

on:
  push:
    paths-ignore: ['website/**']
  pull_request:
    paths-ignore: ['website/**']

and going back to:

on: [push, pull_request]

Tests for binaries are fast enough so it won't be a problem anyway.

[starkos]

I fixed the links and the CI configuration as requested, and also switched to a nicer (IMHO) widget for displaying the sponsors on the download page.