fix write archive bug

[joehand]

Fix the infinite loop bug where writing archive would add a bunch of version files.

[joehand]

Hmmm. This doesn't totally fix it because it still writes the files, updating the mtime which makes it get imported again. I tried setting raf to false raf(name, {writable: !archvie.metadata.writable}) but then hyperdrive complained. Maybe we need to add the indexing option back to hyperdrive.