Modify travis config.

.travis.yml

@@ -4,8 +4,10 @@ python:
     - "2.6"
     - "2.7"
     - "3.2"
+    - "pypy"
 install:
-    - pip install --use-mirrors -r tests/travis/requirements-${TRAVIS_PYTHON_VERSION}.txt
+    - if [ "$TRAVIS_PYTHON_VERSION" == "2.5" ]; then pip --quiet install unittest2; fi
+    - if [ "$TRAVIS_PYTHON_VERSION" == "2.6" ]; then pip --quiet install unittest2; fi
     - python setup.py install
 script:
     - python setup.py test

tests/travis/requirements-2.5.txt

-unittest2

tests/travis/requirements-2.6.txt

-unittest2