[Merge] lp:~flacoste/ubuntu-archive-tools/copy-build-scheduler into lp:ubuntu-archive-tools

[Francis J. Lacoste]

The queue capacity is actually pretty constant, except when HW enablement grabs machine for testing which shouldn't happen during copy rebuilds which require timely processing. (As they are now supposed to coordinate with platform to make sure they don't reduce capacity when it's most needed.) 

Nonetheless, I did move the capacity computing within the loop and it's going to be recomputed every 25 minutes.

I also increase the time between schedule run to 5 minutes. The time we should use is probably around the time it takes for short build to complete. But 5 minutes will probably work fine any way.

Thanks for the review.
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https://code.launchpad.net/~flacoste/ubuntu-archive-tools/copy-build-scheduler/+merge/69370
Your team Ubuntu Package Archive Administrators is requested to review the proposed merge of lp:~flacoste/ubuntu-archive-tools/copy-build-scheduler into lp:ubuntu-archive-tools.