Add Python 3.7 to supported versions

Author: dgalan-xxia

setup.py

@@ -62,6 +62,7 @@ def read(fname):
       'Programming Language :: Python :: 3.4',
       'Programming Language :: Python :: 3.5',
       'Programming Language :: Python :: 3.6',
+      'Programming Language :: Python :: 3.7',
       'Topic :: Software Development :: Libraries :: Python Modules',
       'Topic :: System :: Distributed Computing',
       'Operating System :: Microsoft :: Windows',