contributors: branches being re-arranged as prep for beta launch on 04/11

[petersilva]

Hi folks,

Preparing for change on 04/11 where sr3 becomes the default version people see and get.

• github default branch has changed from main to v2_stable for now (which is basically identical.)
• forked v2_dev off of main, is the new branch for v2 integration work (which was done on main until now.)
• in terms of flow tests, sr_insects branch v03_wip merged with main (travis/flow_autoconfig.sh updated to match.)
• now that the main branch is no longer the default, merging in v03_wip.
• main will become the stable branch for v03 development, going forward.

Launchpad.net changes:

• daily & pre-release repositories' v2 packages are now built from the v2_dev branch (instead of main.)
• for the Release repository, v2 packages are (still) built from the v2_stable branch.
• daily & pre-release repositories` sr3 packages are (still) built from v03_wip.
• for the Release repository, sr3 packages will be built from main (were not built until now.)

GCHR (Github Container Hosting Repository) aka docker images of sr3,

• will be generated from main, rather than v03_wip, so they will be on a stable release cycle instead of tracking development.

on 2022/04/11 the following change will occur:

• github default branch will revert to main, but main will then be showing version 3 code, instead of version 2.
• github metadata will point to the new web-site https://metpx.github.io/sarracenia/ rather than just using rst rendering within the source tree.
• there may be a further release at that point.

[petersilva]

on 2022/11/04, for the C package (sarrac in v2, metpx-sr3c in v3) the branches have also been re-arranged:

• v2 --> development branch for v2 stream.
• v2_stable --> tag for latest release.
• v03 --> dev branch for v3 (now default branch.)
• v03_stable --> tag for latest release in sr3 stream

[petersilva]

obsolete, the branches have been re-arranged since anyways. (see #794)