Add healthmap_country.centroid_override for countries whose centroids are not on land.
Use this field in QC stage 2 - if the location has country precision and its HealthMap country has a centroid_override point, replace the location point with the centroid_override point.
Refactor QCManager for consistency and to move some logging into the QCManager.
Tidy-up following review
Fixes following review
Merge branch 'master' into 228-fixed-centroids

Conflicts:
	src/Common/test/uk/ac/ox/zoo/seeg/abraid/mp/common/dao/NativeSQLTest.java
Merge pull request #168 from SEEG-Oxford/228-fixed-centroids

Snap to fixed centroids of various countries