Better documentation and example usage

[ethanfrey]

The README is a good start, but it would be nice to flesh it out a bit more.

This issue is to collect ideas. I will try to make a PR with some examples that worked for me, as I try to experiment with the client. Especially in interactive mode.

[veqtor]

Things I would like to see:

• Some sort of node-discovery mechanism
• How to inject this light-client into lotion, if not possible, I think lotion should abstract away the tendermint-core dependency and either use this light client or core by (some sort of) dependency injection
• How to package a lotion-js in-browser app using browserify