Revision 2414

Fixing #2698 (transparent polygons are not exported to svg file)

	* Extensions/svgexport/svgmapwriter.py:
	Added verbose variable and some logging depending on it.
	(class VirtualDC(XMLWriter)): Minor improvement in the polygon loop,
	because counting i is not necessary.
	(class Pen, class Brush): Added simple __str__ methods.
	(SVGRenderer.draw_polygone_shape): Fix #2698 (transparent polygons are
	not exported to svg file) Note: holes still unhandled.

	* Extensions/svgexport/test/test_svgmapwriter.py:
	        Made a baseclass TestWithDC for test needed a DC.
		Added tests for bug #2698 (transparent polygons are not
		exported to svg file):
		Testobjectexport.test_transparent_polygon()