Add publish setup.py helper

Author: jpadilla

setup.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python
 import os
+import sys
 import re
 from setuptools import setup
 
@@ -18,6 +19,15 @@ def get_version(package):
     long_description = readme.read()
 
 
+if sys.argv[-1] == 'publish':
+    os.system("python setup.py sdist upload")
+    os.system("python setup.py bdist_wheel upload")
+    print("You probably want to also tag the version now:")
+    print("  git tag -a %s -m 'version %s'" % (version, version))
+    print("  git push --tags")
+    sys.exit()
+
+
 setup(
     name='PyJWT',
     version=version,