Diameter Stack: Make Peer FSM thread count configurable

Fixes Issue 30
Documentation for 'Diameter Stack: Make Peer FSM thread count configurable'

Update Issue 30
Updated documentation
Small improvement to getPeerTable()
Diameter Stack: Limit/Clean Peer Table

Update Issue 3
Status: Fixed
Implemented option 1, with hardcoded size of 10000 peers.
Diameter Stack: Session based Client CCA/Gx/Ro throws Null Pointer Exceptions if send fails in HA mode in getGatheredRequestedAction()

Update Issue 34
Status: Fixed
Fixed the issue in all affected applications and situations.
Diameter Stack HA: Unboxing to primitive type throws NPE when session data does not exist (ie, is null)

Update Issue 33
Status: Fixed
Created util methods to handle null properly. Fixed the return methods in several applications.