Document how to modify deployment functionality

[ThadHouse]

Lots of requests over the years to make things more configurable. This is a list of things that have been asked for.

• Run commands on robot program deploy after deploy but before program start.
• Add to the robotCommands that always run on program startup.
• Add dependencies on specific artifacts
• Create artifacts that run at specific deploy stages.

We should also document the new DeployStage support we have for 2022.