Attempting Q3
split out between t2 and t3
Separated main method out into its own class
Introduced interface for genericising return types in main method test harness
Allowed all tasks to be specified on the command line
ALTERED DOCUMENT SCHEMA

Region document schema altered to have subdocuments for each of the population figures
Refactor Inserter to RegionDAO and changed api for constructor injection
Refactored codec into a separate class for constructor injection
refactored method name
Decoding Regions from DB
Region now calculates the year on year change
Persist the annual population growth
Completed Task 2
Updated output for task2
Added first part of Task3
Task 3 complete