init: octave_kernel at 0.32.0, metakernel at 0.27.5

[thomasjm]

Motivation for this change

Init the Octave Jupyter kernel. Needed to add the Python metakernel package as a dependency as well.

Things done

• Tested using sandboxing (nix.useSandbox on NixOS, or option sandbox in nix.conf on non-NixOS linux)
• Built on platform(s)
  • NixOS
  • macOS
  • other Linux distributions (Ubuntu 20.04)
• Tested via one or more NixOS test(s) if existing and applicable for the change (look inside nixos/tests)
• Tested compilation of all pkgs that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Added a release notes entry if the change is major or breaking
• Fits CONTRIBUTING.md.

[SuperSandro2000]

Please fetch the image files from a remote.

Also please format the new files with nixpkgs-fmt.

[jonringer]

sorry if my latest comments are out of date, looks like I forgot to submit last night

[ethancedwards8]

Result of nixpkgs-review pr 123948 run on x86_64-darwin 1

2 packages built:

• python38Packages.metakernel
• python39Packages.metakernel

[SuperSandro2000]

Also please put each package into one init commit.