decompress database files and use a rolling chunker

[RubenKelevra]

The compressed database files need to be fetched each time there's a change, even if there's just a single package updated.

To avoid this, I like to decompress them and use a rolling chunker with fairly small chunks on it. This way, ipfs can do delta updates on it.

Compared to packages, this is possible because database files are not signed – it just doesn't matter how they are delivered as Pacman will always trust them.

[RubenKelevra]

Necessary to investigate how useful this would be.