Convert taskmasters to use an autoscale pool
Summary: Ref T7352. This is pretty straightforward. I renamed phd.start-taskmasters to phd.taskmasters for clarity.
Test Plan:
- Ran phd start, phd start --autoscale-reserve 0.25, phd restart --autoscale-reserve 0.25, etc.
- Examined PID file to see options were passed.
- I'm defaulting this off (0 reserve) and making it a flag rather than an option because it's a very advanced feature which is probably not useful outside of instancing.
Reviewers: btrahan
Reviewed By: btrahan
Subscribers: epriestley
Maniphest Tasks: T7352
Differential Revision: https://secure.phabricator.com/D11871