try wheels for faster dependency installation

.travis.yml

@@ -1,20 +1,20 b''
 # http://travis-ci.org/#!/ipython/ipython
 language: python
 python:
     - 2.7
     - 3.3
 env:
     - GROUP=
     - GROUP=js
 before_install:
     # workaround for https://github.com/travis-ci/travis-cookbooks/issues/155
     - sudo rm -rf /dev/shm && sudo ln -s /run/shm /dev/shm
     # Pierre Carrier's PPA for PhantomJS and CasperJS
     - time sudo add-apt-repository -y ppa:pcarrier/ppa
     - time sudo apt-get update
     - time sudo apt-get install pandoc casperjs nodejs libzmq3-dev
-    - time pip install jinja2 sphinx pygments tornado requests mock pyzmq
+    - time pip install -f https://nipy.bic.berkeley.edu/wheelhouse/travis jinja2 sphinx pygments tornado requests mock pyzmq
 install:
     - time python setup.py install -q 
 script:
     - cd /tmp && iptest $GROUP