Incomplete work for using Boost.Polygon to compute medial axis
More work to get Boost.Polygon to compile
Semi-working Boost.Polygon medial axis. Hangs after perimeters, though. Needs pruning and chaining
Finished implementing Boost.Polygon medial axis. Some cleanup needed
Fix failing XS test
Updated MANIFEST with Boost files
fixed simple config load bug
fix XS build on Windows #1433 #1681
Bugfix: when processing with fill_density = 0, top/bottom solid shells were missing regions thinner than 3 * extrusion width. Includes regression test. #1602

Conflicts:

	lib/Slic3r/Print/Object.pm
	t/fill.t
Merge pull request #1745 from kelow/master

fix XS build on Windows #1433 #1681
Merge pull request #1742 from treygreer/master

fixed simple config load bug
Fix regression in Config->setenv affecting post-processing scripts. Includes regression test
Perform additional checks before merging solid surfaces (i.e. take flow and fill pattern into account)
Bugfix: crashing when concentric infill produced very narrow loops. #1740

Conflicts:

	lib/Slic3r/Fill/Concentric.pm
Make OpenGL optional for the new parts dialog. #1731
Regression test and incomplete fix for bug affecting wrong spiral vase output. #1773

Conflicts:

	lib/Slic3r/GCode/Layer.pm
Fixed spiral vase regressions. Includes regression tests. #1773
Updated test count in t/shells.t
Fix regression about percent extrusion width not being validated. Includes regression test
Refresh plater canvas when switching presets