[Data catalog] Flesh out dev docs on how to build and test with dbt

[jeancochrane]

We have some barebones documentation in dbt/README.md, but currently it only explains how to install requirements and run some basic build and test commands. We should also document the scope of the project more broadly and explain how to develop it.

Some topics to cover, off the top of my head:

• Motivation & link to design doc
• Link to published documentation
• Development
  • Adding a new data source
  • materialization trickiness
  • [x] https://github.com/ccao-data/data-architecture/issues/108
  • Adding a new model
  • Adding a new test
  • How and when tests are run automatically
  • What to do if cleanup-dbt-resources fails
  • Testing as you develop
  • Debugging this error by clearing the state:

Compilation Error
  dbt found two schema.yml entries for the same resource named location.vw_pin10_location. Resources and their associated columns may only be described a single time. To fix this, remove one of the resource entries for location.vw_pin10_location in this file:
   - models/location/schema.yml

Depends on the final pieces of infrastructure being complete, namely

55 and https://github.com/ccao-data/service-sqoop-iasworld/issues/1.

[jeancochrane]

Related: https://github.com/ccao-data/data-architecture/issues/108