switch setup.py to setuptools, change version number to not have a + sign

setup.py

@@ -1,6 +1,6 @@
 #! /usr/bin/env python
 
-from distutils.core import setup
+from setuptools import setup
 from datetime import datetime
 import os
 import subprocess
@@ -29,7 +29,7 @@ def get_version():
         p = subprocess.Popen(['git','log','--oneline','HEAD~..'],
                 stdout=subprocess.PIPE)
         result = p.communicate()[0]
-        version += '+%s.%s' % (datetime.today().strftime('%Y%m%d'), result.split()[0])
+        version += '.%s.%s' % (datetime.today().strftime('%Y%m%d'), result.split()[0])
     return version
 
 setup(