add rassumfrassum "lsp centralyzer"

[chrisemke]

this is a "lsp centralyzer" used to run more than one lsp at once.

https://github.com/joaotavora/rassumfrassum

maybe it could be like this?

---
name: rassumfrassum
description: Connect an LSP client to multiple LSP servers.
homepage: https://github.com/joaotavora/rassumfrassum
licenses:
  - GPL-3.0
languages:
  - Python
categories:
  - LSP

source:
  id: pkg:pypi/rassumfrassum@0.2.1

bin:
  rass: pypi:rass

neovim:
  lspconfig: rass

[Conarius]

You can try it out yourself first (as described in the CONTRIBUTING.md).
After that you can open a PR and once all checks pass and you get two approvals, it will be merged