Meter status support in metrics collector wire format.
Ignore conflict error when releasing maas nodes
Remove obsolete comment
Refactor InstanceBroker.StartInstance to return result struct

StartInstance will soon need to grow another result for
reporting back block devices allocated to a provisioned
instance. Rather than having to touch every bit of code
each time we expand the set, use a result struct.
Merge pull request #1100 from axw/environs-startinstanceresult

Refactor InstanceBroker.StartInstance to return result struct

StartInstance will soon need to grow another result for
reporting back block devices allocated to a provisioned
instance. Rather than having to touch every bit of code
each time we expand the set, use a result struct.
Comment update
Merge pull request #1095 from voidspace/maas-1381619

Ignore conflict error when releasing maas nodes

When releasing a node that is not in a releasable status, i.e. typically is already released, maas returns an error 409. Instead of dying and refusing to destroy environment we now ignore that error.

Error 409 is only used for a limited set of statuses, so this seems like safe behaviour. See: https://bugs.launchpad.net/maas/+bug/1381619/comments/15

Fixes bug 1381619.
Merge pull request #1076 from tasdomas/wire_format_unit_status

Meter status support in metrics collector wire format.

Meter status updating support in wire format for sending metrics to the metrics collector.