Slider client should accept a separate ZK quorum for applications and a root path within the quorum for application usage

Currently, the zookeeper quorum specified in Slider is used by the Registry service as well as application instances. This is not desirable as Registry needs to be highly available and performant and thus should not compete with applications for resources.

Slider should accept a separate quorum for applications use. When specifying the user should specify a quorum and optionally a path. A child ZK node will be created and will be made available to the application for its use.