Implement MiloDE (diff. expr. testing on top of milo framework)

[stefanpeidli]

Description of feature

Should be relatively easy given that we already have Milo implemented.
See https://github.com/MarioniLab/miloDE for R

[Zethson]

I won't have the bandwidth to work on this feature for a while, but I'm open to accepting PRs from anyone interested in implementing it.