More mostly superficial changes from Mongo -> Redis
URL parsing code
Cursor._mongo -> Cursor._connection
Don't support ObjectID, just string keys
Pass REDIS_URL through to redis-livedata package
Don't support transforms (which depend on minimongo)
Fix typo
Rename mongo-livedata to redis-live in tests & stats
Adapting the tests to be Redis specific
hmset
Import redis_watcher from spike
Redis subscriptions
Make RedisObserver a first-class object; support stop()
hincrby
Support del (and observe)
Test delete of non-existent keys