The QContactCollection class represents a collection of contacts in a manager.
This class was implemented based on QOrganizerCollection.

Change-Id: I5377f9043a66726182b7a0ed7f40733ffe08b619
Reviewed-by: Matthew Vogt <matthew.vogt@qinetic.com.au>
Reviewed-by: Christopher Adams <chris.adams@jollamobile.com>