Spack related modifications
This MR aims at implementing minor changes to answer concerns that were raised in the Melissa spack package PR.
Note: the PR review also raised multiple difficulties:
- there is no Spack package for
plotext
which was hence moved to the dev dependencies, - there is no Spack package for
hostlist
which is used inidr_torch.py
it was hence removed and replaced with our own parser, - some versions are arbitrary (e.g.
torch
) and some are even strictly constrained (e.g.mpi4py
,flake8
andmypy
) these were made flexible.