Variable path thickness for all support layers to avoid over-extrusion.
Supports only in grid cells below the top contacts.
Provision for filtering excessively long perimeter pieces of the support infill lines.
in case two and more bottom contact layers overlap after their extension.
New method modulate_extrusion_by_overlapping_layers() reduces thickness
of an extrusion path where it overlaps in Z with some other paths.
The same trick has yet to be applied to the layers overlapping in Z with
top contact surfaces.
Removed dependency on Perl Math::PlanePath module.
Fixed compilation with Visual Studio and SLIC3R_DEBUG: Visual Studio older than 2015 does not support the prinf type specifier %zu. Use %Iu instead.
C++11 move semantics enabled.
Made sure the C++ fillers are instantiated at the worker threads,
where there are being released.
Extended the FillRectilinear2 to calculate the contour / line intersection
with exact arithmetics, improved robustness and added error handling
and error reporting, if the contours to be filled are not correct.
Added a safe variant of offset(const Slic3r::ExPolygon...), which offsets each loop separately.
New functions "remove_sticks" to remove zero area parts of polygons.
New functions "remove_small" and "remove_degenerate" for polygon clean up.
Extended the C++ supports, those are not finalized yet though.
