Update the README with details on the Matrix spec  process + unstable prefixes
@@ -3,21 +3,10 @@ Contributing to `matrix-spec-proposals`
Thank you for taking the time to contribute to Matrix!
-This repository is for proposals to changes to the Matrix protocol. The process
-for submitting a proposal is spelt out in detail at
-https://spec.matrix.org/proposals (in particular,
-https://spec.matrix.org/proposals/#process).
-
-However, in brief, it amounts to:
-
- 1. Create a [pull request][1] adding a new file to the
- [`proposals`](./proposals) directory, expaining what you think should be
- changed, and why. (Ideally, the file should be numbered according to the
- pull request number, which normally means you need to rename it once you've
- opened the PR.)
-
- 2. Seek feedback on your proposal, for example in
- [#matrix-spec:matrix.org](https://matrix.to/#/#matrix-spec:matrix.org).
+This repository is for proposals for changes to the Matrix protocol. The process
+for submitting a proposal is described in
+[this repository's README](README.md#the-matrix-spec-process) or in further detail at
+https://spec.matrix.org/proposals/#process.
Sign off
--------
