Virtual CLI for demo client

[MaddieM4]

The ideal design for the demo client is probably a CLI with the following features:

• Clever folding of long lines: there should be a difference between log entries, and line breaks, such that a log entry may be multiple lines (with the first line only displayed by default).
• Log filtering
• Notifications
• Tab completion

This is a huge undertaking, and I'd love to figure out a way to do it through incremental tickets merged to master. As I've been reminding myself via #43, and the docopt tickets, long-running branches are incredibly demoralizing if you care about maintaining your Github streak (which is one of the proxies I'm using for continuous progress).

[MaddieM4]

Going to use broco for this. It will be broco's pilot use case.

The code implications are that js-deje and broco will both be git submodules here, and the only "real" code on our end will be the glue between the two (exposing DEJE functionality as broco modules).