Stitch Regions

Clicking this button stitches, for each mesh, all regions on the mesh if it has more than two regions.

Firstly a dialog window is pop up to ask for the "Min Stitching Face Edge Length (mm)" and "Max Stitching Face Edge Length (mm)" parameters, then the regions are stitched if their gaps are less than the "Max Stitching Face Edge Length (mm)" parameter.