Add SFML the Discord Open Source community list

[eXpl0it3r]

Acceptance Criteria

• All of the following criteria must be met:
  • [x] This community is directly tied to an open source project
  • [x] The open source project has an OSI-approved open source license: https://opensource.org/licenses
  • [x] This Discord server is an official channel for the open source project approved by the maintainers of the open source project
  • [x] This Discord server adheres to the Discord Community Guidelines
• One of the following criteria must be met:
  • [x] The Discord server has over 1,000 members
  • [x] The open source project has a repository with at least 1,000 GitHub Stars or some equivalent

Code Review

• All of the following criteria must be met:
  • [x] The "title" field has a commonly identifiable name of the open source project
  • [x] The "inviteCode" field contains a valid invite code (without the full URL), without an expiration date
  • [x] The "githubUrl" field is a fully specified and valid URL starting with https:// and refers to a place where we can easily find your primary open source repositories. GitHub repo or organization URLs (or some equivalent) are acceptable (but not a cloning URL).
  • [x] The "logo" field refers to the correct logo file (double-check the extension)
  • [x] The "quote" field (if included, it is optional) is about your usage of Discord (and not about the open source project itself)
  • [ ] The "quoteSourceUrl" field (if included, it is optional) is a fully specified and valid URL starting with https://

Logo Review

• All of the following criteria must be met:
  • [x] The logo makes use of transparent elements and does not include its own background
  • [x] The logo will look correct when the non-transparent elements are made solid white
  • [x] The logo is a commonly identifiable logo of the open source project
• One of the following criteria must be met:
  • [x] The logo is an SVG file with 72x72 dimensions and has been optimized with svgo (Web UI)
  • [ ] The logo is a PNG file with 144x144 dimensions and has been optimized with ImageOptim (Web UI)

Potential Preview

I created a small preview to see, how it's going to look: