Using `cp --no-preserve mode` ends up losing the executable bit of
previously compiled build scripts. Instead we should ignore the file
ownership, and subsequently make the files writable (since the store is
read only)
* Turns out it is much faster to build up one big regex of the
references to remove and invoking `sed` just once than it is to invoke
it once per reference
* Define a new installation mode which symlinks identical artifacts
against a directory of previously generated ones
* This allows for linear space usage in the Nix store across many
chained derivations (as opposed to using a zstd compressed tarball
which uses quadratic space across many chained derivations)
* This new installation mode is the new default for all cargo based
builds. The previous behavior is still available by setting
`installCargoArtifactsMode = "use-zstd";` on a derivation
* `buildPackage` will continue to use zstd compressed tarballs while
building dependencies (unless either of `cargoArtifacts` or
`installCargoArtifactsMode` is defined, in which case they will be
honored)
