Create role for pantheon

[patcon]

http://www.quora.com/Drupal-CMS/GetPantheon-vs-Omega8-vs-Acquia-pros-and-cons-of-each/answer/David-Strauss-2

cgroups: https://github.com/hw-cookbooks/control_groups

php-fpm:

• https://github.com/priestjim/chef-php
• https://github.com/cocoy/chef-php-fpm
• https://github.com/homemade/chef-php-fpm

redis (instead of memcache):

• https://github.com/gchef/redis-cookbook
• https://github.com/ctrabold/chef-redis
• https://github.com/brianbianco/redisio

nginx: https://github.com/opscode-cookbooks/nginx

[patcon]

https://www.getpantheon.com/news/how-pantheon-scales

[patcon]

cc: @samboyer