Fixed #3334 -- added Python 3.6 support (#3335)

* Fixed #3334 -- added Python 3.6 support

* install py36

* empty commit to retrigger travis

* this is an impressively dumb typo
diff --git a/setup.py b/setup.py
index c5a99be..8419e6a 100644
--- a/setup.py
+++ b/setup.py
@@ -297,6 +297,7 @@
         "Programming Language :: Python :: 3.3",
         "Programming Language :: Python :: 3.4",
         "Programming Language :: Python :: 3.5",
+        "Programming Language :: Python :: 3.6",
         "Programming Language :: Python :: Implementation :: CPython",
         "Programming Language :: Python :: Implementation :: PyPy",
         "Topic :: Security :: Cryptography",