New --perimeter-feed-rate and --retract-before-travel options. Includes some refactoring and fixes.

lib/Slic3r/STL.pm

@@ -89,23 +89,6 @@ sub parse_file {
             $self->_facet($print, $normal, @copy_vertices);
         }
     }
-    
-    print "\n==> PROCESSING SLICES:\n";
-    foreach my $layer (@{ $print->layers }) {
-        printf "\nProcessing layer %d:\n", $layer->id;
-    
-        # build polylines of lines which do not already belong to a surface
-        my $polylines = $layer->make_polylines;
-        
-        # build surfaces of polylines (distinguishing contours from holes)
-        $layer->make_surfaces($polylines);
-        
-        # merge surfaces having a common line
-        $layer->merge_contiguous_surfaces;
-    }
-    
-    # detect which surfaces are near external layers
-    $print->discover_horizontal_shells;
         
     return $print;
 }