Complete rewrite

- Use node_redis as the underlying driver
- Use when instead of RSVP for promises
Add Travis
Merge branch 'node_redis'

Conflicts:
	modules/__tests__/monitor-test.js
	modules/__tests__/sdiff-test.js
	modules/__tests__/subscribe-test.js
	modules/__tests__/sunion-test.js
	modules/client.js
	package.json
	spec/helper.js