Enforced gentle failure
Changed default palette to 'viridis'
Possible to plug numeric and grouped school buildings data into 'Set_DB'
Changed source URL format in Get_Invalsi_IS description
Experimental features: integrated the counts of students by school running time in the 'nstud' workflow; the user can now include safety certifications in the school buldings DB (not active by default since it requires extra computational time other than downloading time)
Minor changes: function 'Get_Shapefile' can now provide either the boundaries or the centroids of NUTS-3 and LAU administrative units; fixed warning message in 'Group_nstud'; 'Map_DB' allows to map municipality data at province level
Removed 'Get_RiskMap' because the input dataset does not appear to be currently available.
Redirected 'Get_AdmUnNames' to a specific repository of input datasets due to changes in provider website.
Removed 'readxl' from dependencies since no xls input files are scraped anymore.