These replace the custom audit_broadcast_cmd code. An additional env
variable MRSK_RUNTIME is passed to them.
The audit broadcast after booting an accessory has been removed.
Audit details
* Audit logs and broadcasts accept `details` whose values are included as log tags and MRSK_* env vars passed to the broadcast command
* Commands may return execution options to the CLI in their args list
* Introduce `mrsk broadcast` helper for sending audit broadcasts
* Report UTC time, not local time, in audit logs. Standardize on ISO 8601 format
Allow the hosts for accessories to be specified by host or role, or on
all app hosts by setting `daemon: true`.
```
# Single host
mysql:
host: 1.1.1.1
# Multiple hosts
redis:
hosts:
- 1.1.1.1
- 1.1.1.2
# By role
monitoring:
roles:
- web
- jobs
```
