Fix name of BSD PyPI classifier (#88)

Author: traversaro

setup.py

@@ -18,7 +18,7 @@
     keywords=['ROS2'],
     classifiers=[
         'Intended Audience :: Developers',
-        'License :: OSI Approved :: BSD',
+        'License :: OSI Approved :: BSD License',
         'Programming Language :: Python',
         'Topic :: Software Development',
     ],