CHORE - Once we go RC or Stable, set main branch back to master

[khawkins98]

Once we go to beta we'll need to ship CSS less often for the EMBL sites and we'll want to show a more stable look, so it makes sense to set the default branch back to master.

Thoughts/considerations:

• We should make the change just after we PR edits for beta.1 from develop -> master
• Shouldn't impact the gitlab-ci setup (develop branch commits still go to dev deploy)
• Travis will still deploy gh-pages on commits to dev
• If we want to change the way that travis or gitlab are running, we'll have to pull those changes in from develop

[khawkins98]

Thinking on this a bit more, maybe we hold off:

1. We have more important things to do
2. I guess as we're still not stable/rc, it's fair for develop to be the main branch

[khawkins98]

Had a fresh look at this one now that we're at RC; here's what I suggest we do:

1. Delete the current master branch as it's very stale
2. Make a new master branch based off the current develop
3. Set the main branch to master
4. Tag future release to the master branch

There may be other things we want to do, but i think that should be enough to "Use master for stable releases"

[khawkins98]

Did some more reading and it makes sense to keep the default branch as develop mostly as all PR will target that branch by default, and that's where we want our PR going -- otherwise I think we'll accidently merge stuff to master and then have to PR master --> develop 😭