Merge pull request pypa#171 from hickford/patch-2

Add link to appveyor Python version list

Author: qwcode

source/code/appveyor.yml

@@ -10,6 +10,7 @@ environment:
 
     # Pre-installed Python versions, which Appveyor may upgrade to
     # a later point release.
+    # See: http://www.appveyor.com/docs/installed-software#python
 
     - PYTHON: "C:\\Python27"
       PYTHON_VERSION: "2.7.x" # currently 2.7.9