README.md lacks usage description

[ghost]

The readme file should have examples of how to use the library as well as an overview of its API.

[ghost]

Also description on how to use PUB/SUB (or if it is supported at all) from a user's process is lacking.

[zuiderkwast]

I've added documentation and example to README. Looks good?

I've noticed that pubsub doesn't work so I must say it isn't supported. It works somewhat in some situation but we will probably change how it works. SUBSCRIBE to two channels (or more) at the same time causes the client to get out of sync, so the following commands get the reply for another command.