Make sure that correcy proxy settings are passed via SSH.

We were getting proxy settings from when the delayed_jobs runs started,
which is not the correct environment for Sledgehammer.
Add support for pulling in recipe-created data bags
Add proper chef_gem support for talking through a proxy, and force our embedded Ruby in the Chef client to use it.
Merge pull request #85 from VictorLowther/port-from-cb2.0

+1 Port from cb2.0