Support for view collation and include_docs

[jay-jlm]

Let me know if this works with view collations.
From my view whenever I emit using the format { _id: myReferencId } and use the include_docs feature, I get back this on the "value" nodes:

value: { _id: 'index:default:IPCA' }

but the data I need comes in the the "doc" nodes, not the "value" nodes, and those seem not to be processed/retained.