Do perimeters one island at time instead of doing all holes before all contours
Fix regression causing retraction restarts to ignore extrusion_axis. Includes regression test. #1547
Fix regression causing toolchange_gcode to crash Slic3r. Includes regression test. #1545
Removed recursion warning in brim
Split objects could not be repositioned in plater. 3D preview and stats were not available too. #1543
Adapt plater to new convex hull
Merge branch 'master' of github.com:alexrj/Slic3r
Merge branch 'stable'

Conflicts:
	lib/Slic3r/Geometry/Clipper.pm
	lib/Slic3r/Layer/Region.pm
Removed dependency on ->object from Region.pm