Fix missing Rails. Fix Java symlink. Increase default cpus to 2.

@craigschneider @ChrisPetr0 @rppatel1007 
I missed the RVM custom attribute for installing Rails that wasn't included in the old chef json, but instead was a modified attributes file. So I added that in. Reordered Java above elasticsearch as that is the required ordering. Added the default_java_symlink recipe to fix Ubuntu referring to the wrong Java version. Updated the patch level of elascticsearch. Updated the config_vagrant to default to 2 cpus. Hard coded the omnibus_chef version.