Carti supports IPFS

[zcstarr]

Summary:
Carti will support IPFS and will run a hosted pinning service for packages to reliably deploy to ipfs.
This will allow users to publish packages to a global distributed repository.

Motivation:
Search is currently difficult to take stock of all the packages that are floating around and require specialized knowledge of the individual package producers. This feature will open the door for package makers to be browse all created packages from the command line and to opt in to including their package to a global repository.

An example use case is I'm looking for python-scikit RISCV bundle, by adding the global repository one can now browse the local index. This will be a bit of a WIP, but I think this will help grow the ecosystem.

Acceptance criteria:
Developers are able to carti publish bundles.json and carti-machines.json and the bundles themselves to ipfs.
Developers are able to retrieve and use ipfs://addresses to resolve machines as they do currently via https.