Bors: bring back "try"


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.)


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