List Python 3.7 in setup

Author: gliptak

setup.py

@@ -42,6 +42,7 @@ def readme():
         'Programming Language :: Python :: 3',
         'Programming Language :: Python :: 3.5',
         'Programming Language :: Python :: 3.6',
+        'Programming Language :: Python :: 3.7',
         'Topic :: Scientific/Engineering',
     ],
     keywords='data',