[Graphics] 2D view "Flip" button

[mbrown1413]

If you've rotated the 3D view around 180 degrees, you're viewing the piece from the opposite side as the 2D view. I'd like a button on the 2D view so it's viewing from the same direction.

The cameras in GridDisplay_camera.ts take the current viewpoint and position the camera in the viewpoint.forwardVector direction. This button would toggle that the camera is positioned in the -1 * viewpoint.forwardVector direction.

Possible icons to use:

• mdi-rotate-right
• mdi-rotate-360
• mdi-axis-z-rotate-clockwise