giscoR 0.5.1

• Use CRAN DOI: https://doi.org/10.32614/CRAN.package.giscoR.
• gisco_get_education(): Fix API entry points.
• Review failing examples.

What's Changed

• Adjust some tests and examples by @dieghernan in #90

Full Changelog: v0.5.0...v0.5.1