merging applicability-performance branch and resolving conflicts
Updating profiler plugin docs and using generic NotImplementedError instead of InvalidUnitTypeForApplicability which is mostly raised by individual plugins
adding manager layer ApplicabilityRegenerationManager class with methods implementing regeneration apis according to consumer criteria and repo criteria
adding applicability regeneration manager to the manager factory
controller layer additions for applicability generation api in consumer as well as repo controller
unit tests for applicability generation manager and controllers
removing unwanted commented lined
Rename the test_applicability_manager test to test_server_managers_consumer_applicability.

This will help us to identify better which Pulp module this test module is
meant to test.
Remove some type specific knowledge from the applicability code.
Remove the unit_type_id from the profiler applicability method.
Stub out new unit-type agnostic applicability code.
Call the Profiler.update_profile() method during profile updates.
adding changed to make applicability regeneration independent of profile and distributor types
a few corrections to applicability generation manager and unit tests
few more minor corrections and unit test updates
removing debug log statement
updating a failing unit test
Merge branch 'rbarlow-skarkmark-applicability-performance' into rbarlow-applicability-performance
Remove a newline.
Merge branch 'rbarlow-skarkmark-applicability-performance' of github.com:pulp/pulp into rbarlow-skarkmark-applicability-performance