Add `LICENSE` and `DEFAULT_LICENSE` arguments to the `PACKAGE_INFO`
modes of the `install` and `export` commands. If not otherwise
specified, the `LICENSE` will be taken from the project's
`SPDX_LICENSE`, if available.
Add support for specifying CPS's supplemental `description` and
`website` attributes. Add ability to inherit these from the `project()`,
similar to how version information can be inherited.
Modify {export,install}(PACKAGE_INFO) commands to inherit version
information from the current project in situations where it seems
reasonable to do so. Add an option to explicitly request inheritance
from a specific project.
This leverages the recently added project(COMPAT_VERSION).
Matthew Woehlke