Make the chef jigs use the new wanted-attrs driven attrib resolver.

This also unifies how the chef solo and chef jigs handle default
vs. normal attributes.
Merge pull request #81 from VictorLowther/pull-req-master-dccf04341e8a02b81a47fd321efe6c0256033410

+2  (crowbar-hacks role :)
CB 2: Make all the things use wants-attrib for smart attribute injection. [7/8]