Build REST pseudo-resources for code tables

The lab module uses the concept table for storing all code lists. Rather than have the developers and sysadmins deal with the concept table, each code list should be exposed as a separate resource ("pseudo-resource"). There should be a common code body, each pseudo-resource should pass it the source ("jsslab") and code from the concept_map table (plus the uuid and parameter if supplied); if there is no uuid, the common code body will then use concept_map to find the concept_set and then provide CRUD/search operations on the concept set.