Add additional classifiers to indicate version support.

Author: amcgregor

setup.py

@@ -59,6 +59,8 @@
 			"Programming Language :: Python :: 3.3",
 			"Programming Language :: Python :: 3.4",
 			"Programming Language :: Python :: 3.5",
+			"Programming Language :: Python :: 3.6",
+			"Programming Language :: Python :: 3.7",
 			"Programming Language :: Python :: Implementation :: CPython",
 			"Programming Language :: Python :: Implementation :: PyPy",
 			"Programming Language :: Python",