Jig Chef refresh node data (read node data from chef, and start pumping it into the jigMap machinery) [2/2]

refresh node data by reading it from chef.
More tests using a dummy jig to follow soonish - at this point this code requires a running chef server 


 .../barclamp_chef/app/models/barclamp_chef/jig.rb  |   19 +++++-
 .../20130103013026_create_chef_admin_instance.rb   |    5 +-
 .../barclamp_chef/lib/barclamp_chef/chef_api.rb    |   63 +++++++++++++++-----
 3 files changed, 67 insertions(+), 20 deletions(-)

Crowbar-Pull-ID: 89106bdfb9fa96ae1d8f334004c9115bf307c306

Crowbar-Release: development