Update data handling for new data format.
Update data handling for new data format.

 - Cache regions by index on the explorer object
 - Add a formatter to the region column that looks up the region name by ID
 - Remove the code that pivoted indicators to properties

unicef/polio,unicef/polio,unicef/rhizome,SeedScientific/polio,unicef/rhizome,SeedScientific/polio,unicef/polio,SeedScientific/polio,SeedScientific/polio,unicef/rhizome,SeedScientific/polio,unicef/rhizome,unicef/polio