Saved queries should always include relation spec (database.schema.alias), and respect generate_x_name macros

[jtcohen6]

We should:

• always include NodeRelation objects for each export (including database, schema_name, alias)
• resolve the database / schema_name / alias with respect to generate_x_name macros (possibly by calling this method)

Testing Considerations:

Will need a migration from previously saved manifests.
Needs to be non-breaking change to artifacts.

Considerations:

May not be able to backport these.

Discussion Summarization:

• Might need to refactor generate_x_name functions to be usable outside of initial parsing
• Might not be able to migrate existing manifests, i.e. they won't get regenerated until reparsed

[martynydbt]

Proposal that this is not required for 1.8

[aranke]

Update from estimation discussion:

1. We can potentially avoid modifying artifacts by only adding the NodeRelation object to the export internal object that is not written to disk.
2. Investigate whether this approach will satisfy A/C of resolving the database / schema_name / alias regarding generate_x_name macros.
3. Document feasibility of writing NodeRelation to artifacts if required.