Generates a 'ear'.
Each of the lateral parts of the module is a 'ear'. Basically, a 'ear' is the convex hull of a cylinder and a cube.
For more info and explanatory images check module documentation.
{
if (shift == 0) shift = 0.001;
Component square = Cube( base, shift, thickness).translate( 0, shift/2.0, 0);
Component circle = Cylinder( radius, thickness).translate(0, height, 0);
return square & circle;
}