[UX] When changing the remote the issue number should be reissued

[Ducasse]

• checkout
• new branch from issue
• type a number like 884
• It was in the wrong repo so you get

• Now change the remote

• you have to retype the number to finally get

So let first recompute the brnahc name when the remote is selected.

In the second issue it would be good to be able to get the right remote on the top :) Should ask @tesonep if this is possible.

[Ducasse]

Oops this is an iceberg issue.