Merge pull request #636 from cloudedge/pull-req-master-1abd9808089136084601124ce81a5817dfe235a6

https://github.com/crowbar/barclamp-crowbar/pull/636

Merged by devtool for VictorLowther
Several changes for core Jig handling:

  * Jig entries in crwbar.yml must declare what class implements them.
  * Jigs are created at barclamp import time, not as part of a
  migration.
  * Jigs can declare what roles need to be present on a node for them
    to be able to take action on a node, and the role addition
    infrastructure will take care of making sure those roles are
    present.
  * Bootstrap and implicit roles will only be added to a node at
  create time if the jigs that implement them are active.
Merge pull request #639 from VictorLowther/pull-req-master-902d456b04f9723fcdadbee1c7540b8a939fc3f1

https://github.com/crowbar/barclamp-crowbar/pull/639

Merged by devtool for VictorLowther
Add a column for discovery data -- this should be used to save data
returned by ohai and similar tools.

Jigs that do node inventory should populate this field opportunistically.
BDD test fixes
add overlay capability for node-role
fix errors and tests detected in BDD