Merge pull request #259 from infosiftr/3.5-windows

Remove Windows variants of 3.5

Author: tianon

.appveyor.yml

@@ -7,8 +7,6 @@ environment:
       variant: windowsservercore-ltsc2016
     - version: 3.6
       variant: windowsservercore-ltsc2016
-    - version: 3.5
-      variant: windowsservercore-ltsc2016
     - version: 2.7
       variant: windowsservercore-ltsc2016