Add Attrib that allows role to state a dependency on another barclamp [1/1]

This pull is incremental work towards allowing us to automatically create
deployments when the system starts.

It leverages the existing attrib approach in a non-distriptive way.

Next steps: need to reflect this in the deployment UI and graph

Unblocked work: can now have deployments interconnect when they are created
using the barclamp.create_proposal & (TBD) barclamp.commit methods.


 crowbar_framework/app/models/barclamp.rb           |    2 +-
 .../barclamp_crowbar/attrib_has_deployment.rb      |   86 ++++++++++++++
 crowbar_framework/app/models/deployment.rb         |    9 +-
 crowbar_framework/app/models/role.rb               |   27 ++++-
 crowbar_framework/config/locales/crowbar/en.yml    |    1 +
 .../test/unit/attrib_has_deployment_test.rb        |  125 ++++++++++++++++++++
 .../test/unit/deployment_model_test.rb             |    6 +-
 7 files changed, 250 insertions(+), 6 deletions(-)

Crowbar-Pull-ID: b6bcdd72045d0459c60208990721f85c435f8338

Crowbar-Release: development