Don’t test python 2.7 against django tip

Author: Pamela McA'Nulty

tox.ini

@@ -13,8 +13,9 @@
 #
 
 [tox]
+# Don't test 'tip' on python27!
 envlist =
-    py27-django{18,19,110,111,111tip,tip},
+    py27-django{18,19,110,111,111tip},
     py34-django{18,19,110,111,111tip,tip},
     py35-django{18,19,110,111,111tip,tip},
     py36-django{18,19,110,111,111tip,tip},