Command improvements

[BaileyChessum]

Commands were implemented pretty hastily for an MVP. We could improve them a bit:

• Write a documentation page on the commands, what they are, how to use them, and a list of each command type and their associated parameters.
• Moving the commands plugin.xml definitions out of teleop_modular_twist, a bodge to fix a weird issue with discovery when splitting up packages to make teleop_core. -- maybe this could be solved with a teleop_modular_commands package to just contain general command definitions, and any infrastructure to call these commands without using ROS2 parameters
• Exposing a logging interface to the commands in configurations
• Change the super verbose configuration steps in the existing commands to use teleop::utils::get_parameter<T>(...)
• Allow commands to be executed from a ROS2 service
  • Invoking command objects spawned and configured with pluginlib and a param file by sending the name to invoke in a ROS2 service
  • Invoking a temporary command by sending values in a ROS2 message