Check for unused parameters in CI

[kylestach]

Description

When we move to the ROS parameter system, we should make sure we have a way to ensure all parameters are used at some point in time (and that all parameters used are actually defined). Otherwise we tend to let parameter files rot, and eventually it becomes difficult to work with the parameters file.

Requirements

1. Mark a parameter globally as "used" every time it is accessed under a particular type of run configuration
2. Add a warning into CI for when we have unused parameters