Download screen: Add releases support status

[audrasjb]

Hi there!
The security team suggests to add some "labels" on the Releases screen:

• Mark as Receiving Security and Maintenance Updates the latest branch (currently 6.1)
• Mark as Receiving Security Updates all previous branches that are getting them (currently from 4.1 to 6.0)
• Mark as Outdated older branches (currently 4.0 and below).

These "labels" could be added right after the branch name on this page.
They may also be used to separate branches in the "All releases" list.

[ryelle]

There was some past discussion about adding extra information to this page:

Each major release is identified with both the version number and its code name.

We don’t have the code names associated with the releases in the current tables. Can we get that from somewhere else in the code?

We don't store that detail in code anywhere, the only data-store used for this page is the files on disk itself, which has lead to some bugs such as https://meta.trac.wordpress.org/ticket/4298

I think we can probably resolve this by storing extra details on disk with the release archives, specifying the codename, date, and possibly the announcement post? (I personally would like to see announcement posts linked from that page)