Ported from ansible 1.2 to 1.3

Removed variables from task names - var expansion in 1.3 changed

Update httpd configuration

Update bundler version to 1.3.5

Add 'rhn_enabled', 'ec2_machine' and 'use_internal_repos' variables

Add AWS EC2 workaround (downgrade libyaml)

Add gcc as rbenv dependency