Create initial disease extent

This includes:

- Add 2 new GAUL code columns to the Locations table, and populate them via Data Acquisition
- Populate the initial disease extent for dengue, using the user-supplied hardcode values for now
- Fixed a couple of existing Data Acquisition bugs in snapping locations
- Split out AbstractSpringIntegrationTests into AbstractCommonSpringIntegrationTests and AbstractDataAcquisitionSpringIntegrationTests.