Update the release lifecycle page to reflect current practices #1200
+37
−48
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This updates the release lifecycle page to more closely reflect our actual releases. This started as an effort to drop the superfluous EOM status, but ended up as a rewrite of the Versioning, Maintenance and Schedule sections since all were depending on each other.
We only make a distinction between maintained and EOL versions. The EOM status adds unnecessary complexity and is misleading, so remove it.
This also cleans up the Versioning section, which was using three major heading (Versioning, Major releases and Maintenance releases) for a small amount of content all on the same topic of how the software we release is versioned. This also cleans up a redundant statement about backporting consensus changes and removes an unnecessary statement about the distinction between minor and major features for backports (which we don't even follow nowadays as far as i know).
Then we rewrite the maintenance version, which was making a distinction between "maintenance end" and "end of life" that we do not follow in practice, and overall makes it clearer and more concise. In this section i also remove some confused language about how we handle security fixes, which is not consistent with our practice, in favour of a general sentence that EOL versions do not receive security fixes and a link to our Security Advisories page which gives more details on this topic.
Wherever i touched i also updated the examples to use newer versions. In some cases i also switched from pointing to the exact major release (X.0) to the major version (X.Y) which is more accurate and also what we already do on the security advisories page.