requirements installs nose 1.1.2 but 1.3.1 is requred

[Chris Johnston]

make test
Starting tests...
Traceback (most recent call last):
  File "/usr/bin/nosetests", line 5, in <module>
    from pkg_resources import load_entry_point
  File "/home/chris/virtualenvs/charmhelpers/local/lib/python2.7/site-packages/pkg_resources.py", line 2720, in <module>
    parse_requirements(__requires__), Environment()
  File "/home/chris/virtualenvs/charmhelpers/local/lib/python2.7/site-packages/pkg_resources.py", line 588, in resolve
    raise DistributionNotFound(req)
pkg_resources.DistributionNotFound: nose==1.3.1
make: *** [test] Error 1