Tweaks to tox config to ensure that unittest2 is installed for python2.6

.travis.yml

@@ -4,11 +4,13 @@ env:
   - TOX_ENV=py26
   - TOX_ENV=py27
   - TOX_ENV=pypy
+  - TOX_ENV=py33
 
 before_install:
   - sudo apt-get update -y
   - sudo apt-get install -y build-essential python-dev
   - sudo apt-get install -y libev4 libev-dev
+
 install:
   - pip install tox
 

tox.ini

@@ -4,9 +4,15 @@ envlist = py26,py27,pypy,py33
 [testenv]
 deps = nose
        mock
-;       ccm
-;       unittest2
+       ccm
+       unittest2
        pip
        PyYAML
 commands = {envpython} setup.py build_ext --inplace
            nosetests --verbosity=2 tests/unit/
+
+[testenv:py33]
+deps = nose
+       mock
+       pip
+       PyYAML