Implement ZFS driver

[yonas]

Would be great to have ZFS support.

[arihant2math]

See also: https://wiki.osdev.org/ZFS
Spec: https://www.giis.co.in/Zfs_ondiskformat.pdf

This spec is actually quite compact, and it's much cleaner than ext4 (no weird feature flags all over the place). Unfortunately there is no good starting point to build off of, so it will be a significant amount of work.

[arihant2math]

It might be worth just working on kernel modules and just loading the zfs driver in, like linux does.