Function divider

divider(a, b?, c?): ((aa:
    | number
    | number[]
    | Point
    | Point3d, bb?: number, cc?: number) => Point)
Returns a function that divides a point:
```
const f = divider(100, 200);
f(50,100); // Yields: { x: 0.5, y: 0.5 }
```
Input values can be Point, separate x,y and optional z values or an array:
```
const f = divider({ x: 100, y: 100 });
const f = divider( 100, 100 );
const f = divider([ 100, 100 ]);
```
Likewise the returned function an take these as inputs:
```
f({ x: 100, y: 100});
f( 100, 100 );
f([ 100, 100 ]);
```
Function throws if divisor has 0 for any coordinate (since we can't divide by 0)
Parameters
- a:
      | number
      | number[]
      | Point
      | Point3d
  Divisor point, array of points or x
- Optionalb: number
  Divisor y value
- Optionalc: number
  Divisor z value
Returns ((aa:
    | number
    | number[]
    | Point
    | Point3d, bb?: number, cc?: number) => Point)
- - (aa, bb?, cc?): Point
  - Parameters
    - aa:
          | number
          | number[]
          | Point
          | Point3d
    - Optionalbb: number
    - Optionalcc: number
    Returns Point