OrbitEstimateSerde to support pickle #215
Description
This is a spin off from #212.
Same description for everything. The purpose of this issue is to allow OrbitEstimateSerde to be pickled. This is not possible because, at the moment, only the from_config of OrbitEstimateSerde is implemented. That's because the opposite operation (to_config) is made quite a bit more complicated due to the Frame management. #86 will immensely simplify this, so wait until it's implement to implement this one.