Add update_hook to application_controller, and use it to drive the on_node_change hook. [1/1]

This pull request adds a couple of new hooks to Role and to the application controller that will be used to drive the provisioner machinery.

 .../app/controllers/application_controller.rb      |  10 +
 .../app/controllers/nodes_controller.rb            | 461 +++++++++++----------
 crowbar_framework/app/models/node.rb               |  12 +-
 crowbar_framework/app/models/role.rb               |   7 +
 crowbar_framework/app/models/run.rb                |  23 +-
 5 files changed, 273 insertions(+), 240 deletions(-)

Crowbar-Pull-ID: e81f07a6be99a0e5da101792c86ed9de0660402b

Crowbar-Release: development