Trove/guest agent communication

Guest agent communication

There are the following issues with the guest agents communication method.

1. Heatbeats are directly written to the infrastructure database
2. Mutiple heatbeats used when one will do. There is no need to send a heartbeat saying the agent is up and one for the database state. We know the agent is up if it is reporting the database status.
3. Uses the same transport as

Phase 1

Remove guest agent from writing heartbeats directly to infra database

Remove heartbeats being written to the database directly via guest agent.

Kenneth Wilke proposed this blueprint https://blueprints.launchpad.net/trove/+spec/taskmanager-statusupdate

It was decided in the weekly meeting to not extend taskmanager to handle this but write another manager called trove-conductor that would handle heartbeat updates to the infra database.