reintroduce python2.6 support

.travis.yml

 language: python
 env:
+  - TOXENV=py26-1.6.X
   - TOXENV=py27-1.6.X
   - TOXENV=pypy-1.6.X
   - TOXENV=py33-1.6.X

pipeline/collector.py

@@ -2,7 +2,10 @@ from __future__ import unicode_literals
 
 import os
 
-from collections import OrderedDict
+try:
+    from collections import OrderedDict
+except ImportError:
+    from django.utils.datastructures import SortedDict as OrderedDict
 
 from django.contrib.staticfiles import finders
 from django.contrib.staticfiles.storage import staticfiles_storage

tox.ini

 [tox]
 envlist =
-    py27-1.6.X, pypy-1.6.X, py33-1.6.X, py34-1.6.X,
+    py26-1.6.X, py27-1.6.X, pypy-1.6.X, py33-1.6.X, py34-1.6.X,
     py27, pypy, py33, py34,
     docs
 
@@ -12,6 +12,15 @@ setenv =
 commands =
     {envbindir}/django-admin.py test {posargs:tests}
 
+[testenv:py26-1.6.X]
+basepython = python2.7
+deps =
+    Django>=1.6.0, <1.7
+    mock
+    jinja2
+    futures
+
+
 [testenv:py27-1.6.X]
 basepython = python2.7
 deps =