Update Practical 3: Point in Polygon to SF, update Creative Commons License
Update to move Practical 3: Point in Polygon from SP to SF, including updating example scripts.
Minor typos and Update license to change to Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International.
Date set for Introduction to Spatial Data and Using R as a GIS course given on Tue 7th and Wed 8th December 2021 for NCRM.