Refactor of WorldBank parser

Make it look a bit more like the others adding configuration properties
and separating functionality in different methods.

Now it validated countries against the CountryReconciler
Left the number of countries in 256
Add every avaliable language description for indicators

Fix some encoding problems noticed while doing it
Change parser to use ISO3 instead of ISO2
Not using unknown countries for WorldBank
Adapt WorldBank importer to new model