`howl`: send `vc00` update at same time as run start

This is following on from https://github.com/ISISComputingGroup/DataStreaming/issues/99

`howl` needs to send a vc00 update, as `kafka_dae_control` does, just after sending a run start.

The veto_names and veto_enabled could be passed in as optional arguments to saluki but for most use cases these will be fixed.

this slightly links in with #81 as we're currently just using --veto-probability with the 0th veto.

Start by comparing how `howl` handles run starts with `kafka_dae_control`, using the linked issue #99 for context and checking #81's veto-probability behavior. Trace the run-start path and make the completion criterion that `howl` sends a `vc00` update immediately afterward, with veto names and enabled state handled as described in the issue.

Written by the indexing model from the issue text.