fix contacts data caching mechanism

fix contacts data caching mechanism

* Substitute  calls to persistence binding's
non existent 'write' verb with 'insert' verb
(part of the current api), eliminating
runtime warnings.
* Update code to conform to v3 bindings:
'afb_service_call_sync' is a deprecated method
for appfw v3 bindings, substitute with the recommended
'afb_api_call_sync' method.
* Rebalance refcount for query object.

Bug-AGL: SPEC-3619
Signed-off-by: Raquel Medina <raquel.medina@konsulko.com>
Change-Id: I1453a86ca24b9e90128d9e8bd2ee8f588fe5faa8