anchor.diff:  Since version 6, SolrCloud has had the ability to query one or more collections via an alternative name. These
   alternative names for collections are known as aliases, and are useful when you want to:
   
  -1. Atomically switch to using a newly (re)indexed collection with zero down time (by re-defining the alias)
  -1. Insulate the client programming versus changes in collection names
  -1. Issue a single query against several collections with identical schemas
  +. Atomically switch to using a newly (re)indexed collection with zero down time (by re-defining the alias)
  +. Insulate the client programming versus changes in collection names
  +. Issue a single query against several collections with identical schemas
   
   It's also possible to send update commands to aliases, but this is rarely useful if the
     alias refers to more than one collection (as in case 3 above).
  
positive.code: * Option for deletion of aliases that also deletes the underlying collections in one step. Routed Aliases may quickly
    create more collections than expected during initial testing. Removing them after such events is overly tedious.
  
  As always, patches and pull requests are welcome!
negative.code: There is no automated means of removing a category. If a category needs to be removed from a CRA
  the following procedure is recommended:
  
  . Ensure that no documents with the value corresponding to the category to be removed will be sent
     either by stopping indexing or by fixing the incoming data stream
  . Modify the alias definition in zookeeper, removing the collection corresponding to the category.
  . Delete the collection corresponding to the category. Note that if the collection is not removed
     from the alias first, this step will fail.
  
  === Limitations & Assumptions
  