Merge pull request #24 from special/master

[libcommhistory] Fix random EventsQuery failures caused by QHash randomization
[libcommhistory] Remove deprecated DraftModel
[libcommhistory] Remove deprecated SMSInboxModel
[libcommhistory] Remove deprecated SyncSMSModel
[libcommhistory] Remove deprecated OutBoxModel
[libcommhistory] Remove deprecated UnreadEventsModel
WIP Basic DatabaseIO stubs
WIP First DatabaseIO implementation, able to add and query groups
WIP Port EventModel to DatabaseIO
WIP Implement EventModels