This provides a proof-of-concept for short term storage for cyclus.
In the direct case, there is a different commodity for each spent fuel such that wet storage may only supply dry storage, and dry storage may only supply the deep geologic repository.
In the open case, there is a single spent fuel commodity and any facility may trade with any other facility. However, the DRE greedy solver performs oddly in this case due to averaging preferences. See CEP26 for more discussion.