Function globals canvas MapStructure Symbol formattedString

Helper method that can be used to create a formatted String using
values extracted from the current model.

SYNOPSIS:

symbol.formattedString(format, model_property_names)

Arguments:
- format: string
- model_property_names: a vector of strings representing the model
property names to be used as arguments

EXAMPLE:

var label = waypoint.formattedString('Waypoint %s: lat %.4f, lng %.4f', [model.id, model.lat, model.lon]);