The MechtronSkel holds the common static elements of the Mechtron together
Since a Mechtron is always an instance created to handle a single
Directed Wave or Init, the Skel is cloned and passed to each
Mechtron instance.
Create a Mechtron by implementing this trait.
Mechtrons are created per request and disposed of afterwards…
Implementers of this trait should only hold references to
Mechtron::Skel, Mechtron::Cache & Mechtron::State at most.