Remove useBootstrap

[neftaly]

This PR removes localStorage (document URL persistence) from useBootstrap. It is intended to enable useBootstrap to be used without a storage adapter, as per #266.

[neftaly]

It would be helpful to show an example of localStorage URL persistence in a tutorial or cookbook or similar

[pvh]

We talked about this a while back but I think we ought to just deprecate useBootstrap entirely. I agree that the localStorage is the pits but the longer I go, the more I lean towards doing away with it. What do you think?

[neftaly]

Sounds good, I would rather this existed in a tutorial or example.

[neftaly]

There is still an example using useBootstrap in packages/automerge-reac-hooks/README.md (and the identical comment on packages/automerge-reac-hooks/index.ts).

I don't have the bandwidth to fix the example though sorry! But it's not urgent and shouldn't affect anything.

[pvh]

I had a heap of rebase conflicts so I just reimplemented this but it's done now. Thanks @neftaly.