Events: persist + display keyword tally

[lukewendling]

fix #119, fix #92

Tasks

• [x] replace word cloud with simple tabular view
• [x] save keyword tallies to event store
• [x] update Loopy with static methods for convenience helpers
• [x] remove unused code in events ui
• [ ] how to test kafka output reliably? currently running against a local kafka docker container

Still a WIP getting a working kafka system to test against. So, I printed input to stdout and reviewed - eyeball tested the would-be output to qcr kafka. Seems to work. I'll take another swing at getting a useful dockerized kafka system running next time i'm in dr-manhattan.

[lukewendling]

@justinlueders ready for final review and merge