UploadWizard config: Add PD-old-70-1923 license

Adding PD-old-70-1923 to UploadWizard upload form.
Per request on
https://commons.wikimedia.org/?oldid=128648006#Adding_more_licenses_in_upload_forms

The current license choice in UploadWizard is purely U.S.-centric. PD-old-70-1923
honors both, U.S. copyright situation as well as that from most other countries.
It is often required for book uploads where authors are not deceased 100 years
ago but the work was published before 1923.

Change-Id: Iffbe65bfa3f8c34d65d1755b86492d05b24db0d4