fix missing requirement for pytz
fix missing requirement for pytz

enbugged when
    Make sure to localize time for date urls
    f0eee30ae0144253d850d4898286867bea846f85

Signed-off-by: Hiroshi Miura <ff6fb3ed059786151e736af13627c08d24e9f922@linux.com>

easton402/pinax-blog,pinax/pinax-blog,swilcox/pinax-blog,swilcox/pinax-blog,pinax/pinax-blog,miurahr/pinax-blog,easton402/pinax-blog,pinax/pinax-blog,miurahr/pinax-blog