Jig Chef refresh node data (read node data from chef, and start pumping it into the jigMap machinery) [1/2]

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 


 crowbar_framework/Rakefile                         |    1 +
 .../app/models/barclamp_crowbar/jig.rb             |   27 +++++++
 crowbar_framework/app/models/jig.rb                |   82 ++++++++++++--------
 crowbar_framework/app/models/node.rb               |    1 +
 .../db/migrate/20120730230714_create_jig_runs.rb   |    2 +-
 .../spec/models/jig_extending_spec.rb              |    6 +-
 crowbar_framework/spec/models/jig_spec.rb          |   79 +++++++------------
 7 files changed, 113 insertions(+), 85 deletions(-)

Crowbar-Pull-ID: 89106bdfb9fa96ae1d8f334004c9115bf307c306

Crowbar-Release: development