Manual rebase of the avoid_crossing_perimeters feature
Make the motionplanner work again after recent changes to approximation
Better implementation of the external motion planner
External motion was crossing still too much
Merge branch 'master' into avoid-crossing-perimeters

Conflicts:
	README.markdown
	lib/Slic3r/ExPolygon.pm
	slic3r.pl
Merge branch 'master' into avoid-crossing-perimeters

Conflicts:
	README.markdown
	lib/Slic3r/Config.pm
	lib/Slic3r/GCode.pm
	lib/Slic3r/Print.pm
	slic3r.pl
Merge branch 'master' into avoid-crossing-perimeters
Restore non-manifold warnings
Little cleanup
Bugfix: --avoid-crossing-perimeters was crashing when processing empty layers
Merge branch 'master' into avoid-crossing-perimeters

Conflicts:
	lib/Slic3r/GCode.pm
Bump version number
Fixed regression causing a long string between copies
Revert "Use G92 to apply Z offset. #486" #778
New wkt() method for debugging
Fixed regression causing first two layers to be infilled with parallel lines
Possible (or at least partial) workaround for the current Clipper segfault. #779
Bugfix: fatal error when using brim and no skirt. #784
Releasing 0.9.5
Bump version number