introduce cluster store

TODO

- [x] Rename Peer to Machine
- [x] Parse the new space separated bootstrap-config format
- [x] Ensure that the NodeName.ID()'s don't have collisions
- [ ] Generate initial cluster ID from a similar hash of the bootstrap-config
- [ ] Write documentation on static bootstrap

Really this method is so simple it doesn't need to exist. On the other hand, we should stop nitpicking and just merge this beast so we stop causing conflicts for brando.