Add Nix cataloger (#1696)

* Add Basic Nix Cataloger

Signed-off-by: Julio Tain Sueiras <juliosueiras@gmail.com>

* Update nix def for the latest syft definition

Signed-off-by: Julio Tain Sueiras <juliosueiras@gmail.com>

* capture nix package files on pkg.NixStoreMetadata

Signed-off-by: Alex Goodman <alex.goodman@anchore.com>

* fix unit tests and linting

Signed-off-by: Alex Goodman <alex.goodman@anchore.com>

* update JSON schema

Signed-off-by: Alex Goodman <alex.goodman@anchore.com>

* address review comments

Signed-off-by: Alex Goodman <alex.goodman@anchore.com>

* Update syft/pkg/cataloger/nix/parse_nix_store_path_test.go

Co-authored-by: Florian Klink <flokli@flokli.de>
Signed-off-by: Alex Goodman <alex.goodman@anchore.com>

* support unstable version conventions

Signed-off-by: Alex Goodman <alex.goodman@anchore.com>

* update json schema relative to main branch

Signed-off-by: Alex Goodman <alex.goodman@anchore.com>

* update syft json with v7.1.1 schema

Signed-off-by: Alex Goodman <alex.goodman@anchore.com>

* fix CLI tests

Signed-off-by: Alex Goodman <alex.goodman@anchore.com>

* remove extra continue statement

Signed-off-by: Alex Goodman <alex.goodman@anchore.com>

* add Nix to list of supported ecosystems

Signed-off-by: Alex Goodman <alex.goodman@anchore.com>

---------

Signed-off-by: Julio Tain Sueiras <juliosueiras@gmail.com>
Signed-off-by: Alex Goodman <alex.goodman@anchore.com>
Co-authored-by: Julio Tain Sueiras <juliosueiras@gmail.com>
Co-authored-by: Florian Klink <flokli@flokli.de>

README.md

@@ -45,6 +45,7 @@ For commercial support options with Syft or Grype, please [contact Anchore](http
 - Java (jar, ear, war, par, sar, native-image)
 - JavaScript (npm, yarn)
 - Jenkins Plugins (jpi, hpi)
+- Nix (outputs in /nix/store)
 - PHP (composer)
 - Python (wheel, egg, poetry, requirements.txt)
 - Red Hat (rpm)