aaa: change location of singletons initialization

InitOnStartup depends on Backend.
By Moving these singletons to Backend post construct method
it  ensures that no bean method will be able to access the singletons
before they are initialized .

Change-Id: I9bab6b42e948fe9eb3d13c236cea810d29c0f745
Topic: AAA
Signed-off-by: Yair Zaslavsky <yzaslavs@redhat.com>