fix: Fix license classifier (#507)

Author: c24t

setup.py

@@ -50,7 +50,7 @@
         release_status,
         "Environment :: Web Environment",
         "Intended Audience :: Developers",
-        "License :: OSI Approved :: BSD",
+        "License :: OSI Approved :: BSD License",
         "Operating System :: OS Independent",
         "Programming Language :: Python :: 3",
         "Programming Language :: Python :: 3.5",