Use procedural decoupler module + texture sets.

On second thought, I would rather -not- make this part until I am ready to work on the probe parts. A single procedural probe-core part does me no good.

Will be delaying this until the Probe-Core series of parts are designated to be worked on, and it will be a set of proper (resizable) probe bodies with all necessary bits included (antenna, reaction wheel, RCS+fuel) where the user can merely supply their scientific payload (experiments). Intend on creating multiple body variants for solar, RTG, or user-supplied power-generation methods.