Doesn't detect develop branch rename

[mcast]

The basic problem is that poor choices of the develop branch name are hard to fix.

• History: We started out calling the branch to which features are merged dev instead of develop.
• The immediate problem: git hf init fails to recognise dev as the develop branch. Instead it chooses master and then breaks because develop and release are the same (fair enough), and leaves a partial configuration.
• In trying to make this easier: if we rename the branch on GitHub (git push origin dev:develop, change the default branch, git push origin :dev) then git hf update doesn't detect this and will no longer see development updates in that clone.

We could insist everyone re-clones, and leave the old clones broken. Hopefully this would eventually become obvious in each case.

Or we could cook up a set of commands to rectify the problem.

The tricky bit is making sure we catch all clones for all developers across all the projects where we chose the unfortunate name. I think we would first have to fix hubflow so it detects that remotes/origin/dev has gone away, and then prompt for remedial action of some sort.

Any suggestions please?