- Adopt standardized short identifiers from the SPDX License List,
see http://spdx.org/licenses/
- Add SPDX-License-Identifier in the source header, see ESR’s
endorsement in http://esr.ibiblio.org/?p=6867
- Print a message telling the user which license is actually chosen
TODO: Work-in-progress, not ready for commit. Comments welcome!