Framewise displacement calculations, CLI, and perhaps, plotting module

[oesteban]

It'd be great to have some transform analysis module, with a CLI so, given a transform at the input, the FD is calculated (and transform parameters written out in a tsv file?)

A good starting point for this could be NiFreeze's registration.utils module: https://github.com/nipreps/nifreeze/blob/26dd2ad5e387f30b96ad787fdcdb7940c4412597/src/nifreeze/registration/utils.py