Extra GPS data like accuracy


Location is enhanced with two new extra fields: accuracy and z coordinate.
These fields are visible from UI and are read-only in web. They are editable only from listly and api.

To fill these values use the following format – accuracy;x,y,z[,color || ,{markercode}].
            var locationField = Api.ItemFields.Read(itemId, "CF" + cFieldId);
            locationField.Value = string.Format("{0}{1},{2}{3}{4}",
                accuracy.HasValue && accuracy > 0 ? accuracy.ToString() + ";" : string.Empty,
                z.HasValue ? "," + z : string.Empty,
                !string.IsNullOrEmpty(color) ? "," + color : string.Empty);

If user changes location from UI, z and accuracy are cleared.
Also sorting on location field is performed by accuracy then by x,y,z.
New parameter called "timeout threshold" added to map tab.
Accuracy threshold moved to map tab.
Both are exposed to listly.

Existing scripts that are hard coded to use the order of the data need to be modified.