Dropped color_factory class in favor of single color_parser function. Moved implementation to new color_factory.cpp since it is odd to have two headers (color.hpp, color_factory.hpp) and only one source file.
+ mapnik::geometry_iterator was replaced by mapnik::svg::path_iterator
+ svg::path_output_grammar was simplified
+ the container for this grammar is now coord_transform2, instead of geometry
+ added typedef size_type to coord_transform2 and removed it from geometry
