[qtcontacts-sqlite] Do not promote origin metadata details

They are specific to the contact instance they are created for.
[qtcontacts-sqlite] Allow multiple aggregates to aggregate unique details

A detail URI should be able to be aggregated into multiple aggregates
without causing uniqueness errors.
Fix date time comparison in aggregation test
Merge pull request #73 from matthewvogt/origin-md-bypass

Fix restrictions which prevent telepathy contacts from being merged together