Store layer slices and region slices as XS data to save memory and make them shared across threads
Merge branch 'master' into xsdata
Bless arrayref representation into Slic3r classes
Merge branch 'master' into xsdata
Implement ExPolygon::XS->clone()
Have Clipper.pm only return ExPolygon::XS objects
Merge branch 'master' into xsdata

Conflicts:
	xs/xsp/ExPolygon.xsp
One more arrayref conversion
Partial GUI compatibility with XS data
New ->scale() method for ExPolygon::XS
New ->translate() method for ExPolygon::XS
Add thread cleanup to avoid double destruction of shared XS data
More incomplete work to make the plater work with XS data
ExPolygon::XS->rotate()
Make plater work with XS data in single-thread environment
Make threaded perls work with XS data in plater thumbnails. Includes cleaner ->arrayref implementation
Merge branch 'master' into xsdata

Conflicts:
	lib/Slic3r/GCode.pm
	xs/src/Point.hpp
Fix merging error
Ported Slic3r::ExPolygon::Collection to XS
Ported Slic3r::Surface to XS