Text changes for better handling of PD and nonfree licenses

Bug: T70687
Change-Id: I84e0094559e5b438fcb33b8511dc0184435c1a37
Mingle: https://wikimedia.mingle.thoughtworks.com/projects/multimedia/cards/1004
Mingle: https://wikimedia.mingle.thoughtworks.com/projects/multimedia/cards/631
Merge "Text changes for better handling of PD and nonfree licenses"