Determine the non-legacy PAP scalability strategy.

Scaling up to more than 1 PAP instances has side effects as new PDPs register.  When a PDP registers, STATE_CHANGE and UPDATE commands are sent multiple times to the PDP (more exactly one for each PAP).   It needs to be determined if there are negative side-effects, for example due to race conditions (for example PAP1 may place the PDP in ACTIVE , while PAP2 may put it back in PASSIVE, to later put it back in ACTIVE).

The work here is determine the best strategy to handle these scenarios.