Support the new AcutalLRP lifecycle

* Small rewrite of lrp_bbs_test wrt DesireLRP
The tests for this method were all over the place; now they live near
each other.

* ActualLRPStateStarting -> ActualLRPStateClaimed
* add CreateActualLRP, Unclaimed state, Validation of unclaimed actual lrp
* Return single instances for ProcessGuidAndIndex methods
* Actual LRP states are now strings
* Prune does a CAD for leaves and then deletes dirs
* LRP convergence handles unclaimed ActualLRPs
* ClaimActualLRP replaces ReportActualLRPAsStarting
* StartActualLRP replaces ReportActualLRPAsRunning
* Single instance return values use pointers
* Use pointers to easily determine when an instance is not found
* Receptor only stops one instance at a time
* Small rewrite of lrp_bbs_test wrt DesireLRP

[#83638702]

Signed-off-by: Eric Malm <emalm@pivotal.io>