Change rs-machine_tag to rightscale_tag
Update collectd repository to point to a branch
Remove rightscale_tag repository from Berksfile now that its published to community
Upgrade test-kitchen and set the concurrency to 4.
Merge pull request #17 from rightscale-cookbooks/white_14_02_acu112203_update_rightscale_tag_repo

Change rs-machine_tag to rightscale_tag