Metadata dependencies

While OpsWorks uses Chef Solo, the cookbooks don't declare proper dependencies where required. This is okay under solo because all the cookbooks must be sent to the node (which OpsWorks handles). However, if one were to use these cookbooks with a Chef Server, the client would not have the right cookbooks available.

Also, the build-essential is listed as a dependency of ruby_enterprise, but it is not in the repository. I added a version of the build-essential cookbook that works in my testing.