CDE doesn't allow Collection Readers to be added to an Aggregate

[Burn Lewis <bu...@gmail.com>]

Aggregates can now contain Collection Readers (they are wrapped as a
CasMultiplier that ignores the input CAS) but the CDE doesn't allow them to
be added.
  "descriptor is not an Analysis Engine or a CAS Consumer or a Remote
Service"

If already in an aggregate the CDE doesn't complain, but won't show their
parameters so overrides cannot be created.

Section 1.3.2 of Tutorial states that "AEs can also contain CAS Consumers"
but makes no mention of CRs. They're discussed in the CPE section.

Should we fix the CDE and docs?  Or remove the wrapper support and provide a
tool/example of how to convert a CR to a CasMultiplier?  Or just  document
this limitation?

I've created Jira 854 to track this.