Allow users to join two different shapes; or split one shape into two pieces.

- Select two segments need to join together;
- Select tool;
- Click the fixed point of the first shape and the one of second shape (hold down Shift key to save the style line)

- Select the style line and all the segments that are on on side of the shape need to be split (must be a closed contour);
- Select tool;
- Click on the style line.

New in V7.0

Allow users to split the pattern piece with seam allowance.