This PR allows the scheduler to replace lost allocations even if the job
has a failed or paused deployment. The prior behavior was confusing to
users.
Fixes https://github.com/hashicorp/nomad/issues/2958
This PR resolves a bug in which a job with multiple task groups would
create new deployment objects each, thus clearing out all other task
groups deployment state.
This PR fixes the rolling update limit calculation to avoid a panic when
there are more allocations for a deployment that haven't determined
their health than the max_parallel count of the task group.
Fixes https://github.com/hashicorp/nomad/issues/2820
