* feat: add a BSD tar toolchain
@thesayyn discovered that it has a feature which should make it a drop-in replacement for pkg_tar
including fine-grained file permissions and symlinks:
https://man.freebsd.org/cgi/man.cgi?mtree(8)
* show example of mtree usage
* feat: introduce tar rule
* cleanup and get test passing
* more cleanup
* chore: add support for compress flags
* chore: add docs
* chore: add docs
* feat: implement linux bsdtar toolchain (#566)
* chore: improve target naming
* WIP: args
* feat: generate mtree spec
Also allow arbitrary args
* refactor: mtree is required
* refactor: style nits
* fix: support mix of source and generated artifacts
* feat: demonstrate strip_prefix
* chore: regen docs
* fix: make host toolchain a fallback toolchain
* fix: include libarchive13.so when installing BSD tar
* chore: buildifier
* fix: aarch64 cpu constraint
* fix(ci): include libarchive13.so when running tar
* chore: add libnettle
* refactor: inputs mutated less
* refactor: remove unneeded substitution arg
* refactor: don't advertise unsupported modes
* fix: hack enough to make it run on my machine
* chore: dynamic libraries included in sh_binary under toolchain
* make sh_binary work
* refactor: drop arm64 for now
* fix toolchain
* fix test
* chore: improve test naming scheme
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Co-authored-by: Sahin Yort <thesayyn@gmail.com>
