48 add support for h5 input format

I just tested and fixed h5 reading.

PR checklist

[x] This comment contains a description of changes (with reason).
[ ] If you've fixed a bug or added code that should be tested, add tests!
[ ] If necessary, also make a PR on the nf-core/scdownstream branch on the nf-core/test-datasets repository.
[ ] Make sure your code lints (nf-core lint).
[ ] Ensure the test suite passes (nextflow run . -profile test,docker --outdir <OUTDIR>).
[ ] Check for unexpected warnings in debug mode (nextflow run . -profile debug,test,docker --outdir <OUTDIR>).
[ ] Usage Documentation in docs/usage.md is updated.
[ ] Output Documentation in docs/output.md is updated.
[ ] CHANGELOG.md is updated.
[ ] README.md is updated (including new tool citations and authors/contributors).