Add 'libhts-dev' and 'tabix'

Add 'libhts-dev' and 'tabix' for iscream: https://github.com/Bioconductor/Contributions/issues/3877

- [x] Install `tabix`, `libhts-dev` on nebbiolo2
- [ ] Install `tabix`, `htslib` on lconway, kjohnson3
- [ ] Add to Ubuntu files
- [ ] Add to mac files

Note: mac suggests using `brew`. Is there an alternative installation?