mapwidget.qml: use map.newZoom and map.defaultZoomIn

When centering on a map location, use the predefined zoom
map.defaultZoomIn.

Later the map should be able to center on (0, 0) and zoom-out
if a dive doesn't have GPS data.

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

mobile-widgets/qml/MapWidget.qml

@@ -80,7 +80,7 @@ Item {
 			NumberAnimation {
 				target: map
 				property: "zoomLevel"
-				to: 17
+				to: map.newZoom
 				duration: 3000
 				easing.type: Easing.InCubic
 			}
@@ -89,6 +89,7 @@ Item {
 		function centerOnMapLocation(mapLocation) {
 			map.newCenter = mapLocation.coordinate
 			map.zoomLevel = 2
+			map.newZoom = map.defaultZoomIn
 			mapAnimation.restart()
 			mapHelper.model.selectedUuid = mapLocation.uuid
 		}