Normalize Duplicate Sources
normalize_duplicate_sources.Rd
Filter out overlapping sources for the same `disease/nesting_disease/basal_disease`, `period_start_date`, `period_end_date` , and `iso_3166_2`, with the choice to keep either national level data (i.e. from Statistics Canada / Dominion Bureau of Statistics / Health Canada) or provincial level data (from a provincial ministry of Health).