rOpenGov/regions: 0.1.8 regions: working with sub-national statistics. Performance improvement
This is minor fix to a performance issue with the recently released version 0.1.7.
Removing a bottleneck from validate_geo_code(). The NUTS exceptions are essentially constants, and it was unnecessary to calculate them each time these functions were running. They were moved to the nuts_exceptions dataset.
Citation info was given the the vignette articles.
Some error messages in assertions were made clearer are more consistent.