remove --use-mirrors from travis install

Signed-off-by: BlackEagle <[email protected]>

Author: BlackIkeEagle

.travis.yml

@@ -13,5 +13,5 @@ before_script:
 - export DISPLAY=:99.0
 - sh -e /etc/init.d/xvfb start
 - bundle install
-install: pip install -r requirements.txt --use-mirrors
+install: pip install -r requirements.txt
 script: bundle exec rake travis