Bors: bring back "try"


#1

Recently I see quite frequent usage of r+ despite the PR is still incomplete. We should bring back the “try” command so it doesn’t confuse people when rolling up.

Basically I think this can be done by whitelisting “try” branch in Travis and AppVeyor. Correct me if I’m wrong. (The deployment has a separate condition, and just keeping it there will avoid “try” from uploading artifacts.)


#2

Right now we unfortunately just don’t have capacity for try, neither AppVeyor nor Travis has extra builders really to run tests. This means that if we enable such a feature we’re basically just blocking the queue, which is basically equivalent to just r+'ing it anyway.


Proposal: move to bors-ng