[Packaging] Allow a user to kill existing builds

[asfimport]

Reporter: Phillip Cloud / @cpcloud

_{Note: This issue was originally created as ARROW-2941. Please see the migration documentation for further details.}

[asfimport]

Neal Richardson / @nealrichardson:
I'm not sure what exactly this is asking for, but packaging has changed a bit in the 2 years since this was reported. Please open a new issue if there is still a problem.