+ comment out as msvc++ doesn't support 'noexcept'
* restore operator%= support - explicit pnoenix::construct<mapnik::expr_node> on rhs
* move fwd decl into main mapnik namespace
* c++ style formatting
+ prefer ```const& ``` style (mapnik c++ style)
Geometry/Feature parsers -truncate 'where' message in on_error handler (currently 16 chars max)
+ add feature_parser.cpp
+ cleaup old comment
+ add from_geojson static method

TODO: better handling of feature.id() and transcoder
+ add feature_parser implementation