Fix how we detect and bail out of IPMI detection.
Clean up metadata.rb per Rob's feedback.
Drastically refactor and simplify IPMI discovery and config.

* Refactor the discover and configure recipes with an eye towards
  simplicity and longer-term maintainability.
* Add a library of helper functions in an IPMI module.
* Kill off the now-redundant resources and providers.
  RHEL 6 ipmitools is smart enough about timeouts to no longer require
  the weird ad-hoc test/set/sleep/test thing we were doing with them.
* Add a bunch of attributes to expose IPMI information we care about to
  everyone else.
Merge pull request #1 from VictorLowther/working-ipmi-config

Working ipmi config
Let the Crowbar framework manage Nodes via IPMI

Now that we can detect and configure IPMI, let's start using it!

* Add a slew of IPMI-related attributes for the framework to use.
* Make sure we actually enable LAN access for IPMI commands.
* Add a Power subclasd for the core to use to send power commands
  without it having to know it is using IPMI.
Merge pull request #2 from VictorLowther/add-plugin-for-core-power-management

+2 Let the Crowbar framework manage Nodes via IPMI
Smoked on physical and virtual.
CLI demo worked
Pull in the openwsman repository.

When we start adding the wsman jig, we will need all the openwsman bits,
so go ahead and preemptively pull them in.
Add a little more verbosity to the IPMI discovery recipe.