[OE-core] Thud community support

[akuster808]

The Poky thud branch is now under 'Community support' and is seeking a
maintainer to continue supporting the following repos for the thud release:

bitbake, core, meta-yocto and yocto-docs.


There will be no more point releases.

see
https://wiki.yoctoproject.org/wiki/Stable_Release_and_LTS#Maintainer_Procedures 
to get an idea on what is expected.

The one thing we (YP) don't know is if there will be AutoBuilder
resources available.  Please contact me or Richard regarding that statement.

If no one steps up by April 24th (six weeks -ish from now), Thud will be
moved to EOL status.

- Armin