supporting simple module deployment

this is just a stepping stone commit, still requiring a lot of rework

does not yet support options values, composed modules, jobs, or source/sink channels

Added ZooKeeperStreamDefinitionRepository

That is now instantiated within both redis-store.xml and memory-store.xml.

It will later be expanded to supplant those (the --store option will no longer be necessary).

The /streams endpoints in the REST API are now backed by this implementation.

Added support for Module undeployment

Implemented ZooKeeperStreamDefinitionRepository findAll methods needed to support 'stream list'

Removed RedisStreamDefinitionRepository and InMemoryStreamDefinitionRepository

Tests (work in progress)

Stream delete functionality

Introduced the ability to undeploy and delete a stream.
The Stream object has a new property in its map to
determine if the stream's modules should be deployed
upon creation. This property is exposed through
a "getter" in the Stream object and is examined
when a stream is created or updated in ZK.