typedef the internal type

Change-Id: I11e785427add72b56bc48cfac1640211dfba6cc6
create factory function for encapsulation

Change-Id: I4cf6ca2855787102f6f9edd477e0d6e4c6a43503
decouple CntntStore so it can be refactored

Change-Id: I26554a0e269d63830fd84b37a4323f40c80fc014