maplocationmodel: add a "selectedUuid" property to MapLocationModel

Inside the QML Map class there is a MapItemView item.
This item uses a delegate that receive a "model" property from
the MapLocationModel, but infact that's a QObject with the MapLocation
defined properties. That's how MapItemView works.

The problem here is that "model" QObject cannot be cast back
to a MapLocation as the meta data in there does not include
a MapLocation sub-class, for some reason.

Even if using propery() on that QObject to fetch data like coordinates
works, instead of storing this strange object pointer, store the
MapLocation UUID (from dive_site) which is a uint32_t.

setSelectedUuid() deals with this oddity and finds the correct
MapLocation pointer in the table and dispatches a selectedLocationChanged()
signal for it.

Signed-off-by: Lubomir I. Ivanov <neolit123@gmail.com>

qt-models/maplocationmodel.cpp

@@ -92,3 +92,19 @@ void MapLocationModel::clear()
 	m_mapLocations.clear();
 	endRemoveRows();
 }
+
+quint32 MapLocationModel::selectedUuid()
+{
+	return m_selectedUuid;
+}
+
+void MapLocationModel::setSelectedUuid(quint32 uuid)
+{
+	m_selectedUuid = uuid;
+	MapLocation *location = NULL;
+	foreach(location, m_mapLocations) {
+		if (location->getRole(MapLocation::Roles::RoleUuid) == uuid)
+			break;
+	}
+	emit selectedLocationChanged(location);
+}