build provisioning server

[warner]

The "provisioning server" will be a (probably python-based) webserver that offers demo users the ability to get access to a bundle of demo resources. It will offer a form that says "click here to join the demo", which presents a magic-wormhole invitation code. On the client side, they run some demo-setup tool that we need to write, which uses that code to build a connection with the provisioning server, and exchange two things: their newly-minted ag-solo node's public key is traded for a configuration blob that includes the chain's GCI, the ipaddr/port of all the validator nodes (used as tendermint RPC servers), and the ingress index they should use in their bootstrap.js to access the demo objects.

The provisioning server will then use its localhost HTTP access to a controller ag-solo node to deliver a provisioning request to the chain vat objects. These objects will create the demo objects, then register them with the comms vat in a new egress, tied to the client's public key. Then the provisioning server will send the chain info to the client, and the client will configure its own bootstrap.js file before running ag-solo start.

[michaelfig]

Note that the provisioning request should validate that the public key doesn't already have a corresponding egress.

[warner]

This looks good, I think we can close this now.

[warner]

in the old repo. this was cosmic-swingset issue 10