Remove now unneeded custom license field in setup.py

Author: saxbophone

setup.py

@@ -49,7 +49,6 @@ def retrieve_deps(filepath):
     url='https://github.com/saxbophone/basest-python',
     author='Joshua Saxby',
     author_email='joshua.a.saxby@gmail.com',
-    license='Copyright 2016 Joshua Saxby',
     classifiers=[
         'Development Status :: 3 - Alpha',
         'Intended Audience :: Developers',