Added ChartObjectDescriptor, DrawingObjectsExport classes for exporting drawing objects created by 3rd party indicators.
Explicitly supported drawing tools are: ArrowDown, ArrowUp, Diamond, Dot, Region, Square, Text, TextFixed, TriangleDown, TriangleUp
These drawing tools and the rest of drawing tools can be distinguished by tag, display text property, and color.
Strategies
Added DrawingObjects_Export strategy. Export settings are defined in .xml file. Download sample xml settings.