Fix missing LICENSE file in cramjam-cli

[musicinmybrain]

Add a symbolic link to the top-level license file, and configure maturin to include it (dereferenced, as a regular file) in sdists and bdists/wheels.

Before:

The sdist on PyPI, cramjam_cli-0.1.1.tar.gz does not contain the license text (but the chosenMIT license requires the license text to be distributed).

After:

Both sdist and bdist (wheel) contain LICENSE as a regular file.

$ python3 -m build
$ tar -tzvf dist/cramjam_cli-0.1.1.tar.gz 
-rw-r--r-- 0/0             268 1969-12-31 19:00 cramjam_cli-0.1.1/cramjam-cli/Cargo.toml
-rw-r--r-- 1000/1000      1070 2023-11-13 12:03 cramjam_cli-0.1.1/cramjam-cli/LICENSE
-rw-r--r-- 1000/1000      1136 2023-11-13 12:03 cramjam_cli-0.1.1/cramjam-cli/README.md
-rw-r--r-- 1000/1000      7182 2023-11-13 12:03 cramjam_cli-0.1.1/cramjam-cli/src/main.rs
-rw-r--r-- 1000/1000      2244 2023-11-13 12:03 cramjam_cli-0.1.1/cramjam-cli/tests/test_cli.py
-rw-r--r-- 1000/1000     34478 2024-02-15 12:31 cramjam_cli-0.1.1/Cargo.lock
-rw-r--r-- 0/0             213 1969-12-31 19:00 cramjam_cli-0.1.1/Cargo.toml
-rw-r--r-- 0/0             618 1969-12-31 19:00 cramjam_cli-0.1.1/pyproject.toml
-rw-r--r-- 1000/1000      1070 2023-11-13 12:03 cramjam_cli-0.1.1/LICENSE
-rw-r--r-- 0/0            1698 1969-12-31 19:00 cramjam_cli-0.1.1/PKG-INFO
$ python3 -m wheel unpack dist/cramjam_cli-0.1.1-py3-none-linux_x86_64.whl
$ find cramjam_cli-0.1.1/ | sort
cramjam_cli-0.1.1/
cramjam_cli-0.1.1/cramjam-cli
cramjam_cli-0.1.1/cramjam_cli-0.1.1.data
cramjam_cli-0.1.1/cramjam_cli-0.1.1.data/scripts
cramjam_cli-0.1.1/cramjam_cli-0.1.1.data/scripts/cramjam-cli
cramjam_cli-0.1.1/cramjam_cli-0.1.1.dist-info
cramjam_cli-0.1.1/cramjam_cli-0.1.1.dist-info/license_files
cramjam_cli-0.1.1/cramjam_cli-0.1.1.dist-info/license_files/LICENSE
cramjam_cli-0.1.1/cramjam_cli-0.1.1.dist-info/METADATA
cramjam_cli-0.1.1/cramjam_cli-0.1.1.dist-info/RECORD
cramjam_cli-0.1.1/cramjam_cli-0.1.1.dist-info/WHEEL
cramjam_cli-0.1.1/cramjam-cli/Cargo.toml
cramjam_cli-0.1.1/cramjam-cli/LICENSE
cramjam_cli-0.1.1/cramjam-cli/README.md
cramjam_cli-0.1.1/cramjam-cli/src
cramjam_cli-0.1.1/cramjam-cli/src/main.rs
cramjam_cli-0.1.1/cramjam-cli/tests
cramjam_cli-0.1.1/cramjam-cli/tests/test_cli.py

[milesgranger]

Thanks @musicinmybrain! 💯