Set license from __init__.py

This fixes pip so it displays the correct license for the package.

Author: ccorbacho

setup.py

@@ -50,6 +50,7 @@ def run_tests(self):
         author=metadata['author'],
         author_email=metadata['email'],
         url=metadata['url'],
+        license=metadata['license'],
         cmdclass={'test': PyTest},
         setup_cfg=True,
     )