Mark a subpath only as closed if it is followed by a move_to or noting (and minor clearifications)
Don't make assumptions about the length of RSVGPathData segments
Discard a path if it only contains a move_to (and minor cleanups)
Implement path helper functions rsvg_path_get_segment_direction and rsvg_path_points_not_equal.
These are to be used by the marker code, and (todo) by the code that draws square linecaps on zero-length path segments.
Rewrite rsvg_render_markers to operate on RSVGPathData paths