fix requirements

- remove requirement on current dev version of ansible (1.2), latest
  distributed packate is 1.1
- don't install distribute, horks your virtual environment

ansible-requirements.txt

 Jinja2==2.6
 PyYAML==3.10
-ansible==1.2
+ansible
 argparse==1.2.1
 boto==2.8.0
-distribute==0.6.24
 paramiko==1.10.1
 pycrypto==2.6
 wsgiref==0.1.2