Initial gem

Created by bundle gem
add some dependencies
initial skeleton

publisher and subscriber can communicate
pusher and puller can communicate
add authenticator client and server

uses req/rep sockets to handshake
add persister actor

interfaces with redis (or a redis proxy)
add cli skeleton using thor
add some certificate wrangling commands

generate certificate authorities and client certs, plus verify client
certs with the CA.
settings class and example
add jsonrpc mechanism

So far just used by the handshake mechanism, but eventually for all
messaging.
add certificate handling and shared key exchange

Client and server exchange certificates and both verify with the CA
certificate.

Shared key exchange works now. The shared key is encrypted using the
public key sent by the client, so only the client can decrypt it.
notes on default settings
get ssl strings from settings
rename client/server authenticator classes

Server::Authenticator => Server::Keymaster
Client::Authenticator => Client::Keyslave
notes about jsonrpc subclasses
generalize request and response handlers

The Keymaster and Keyslave classes are now generic request/response
dispatchers, delegating requests and responses to method-specific
handlers.

This makes it easier to add more request/response RPCs in the future.
send configured client name
ignore pem files
more notes on redis commands used
terminate requester actor if server doesn't respond

This may not end up being the right thing, depends on how zmq sockets
behave