Use Integration for R/E/L

Now that the MasterReference.Patient R/E/L groupings are production-ready, this branch changes the source of the mapping from a bespoke crosswalk to the enterprise preferred source. The source in Integration leverages the original code here, so this is effectively a no-op change to the data.

Going forward, PatientDemographic will remain aligned with Integration. The PatientDemographic view can still be used if easier for analysts, without worrying about the difference in sources.

This change also retains some backwards compatibility to the original code, mainly the values are Title Case instead of ALL CAPS, and Unknown/Missing remains Unknown. This latter piece is likely to change in the future to remain aligned with Health Equity standards.