Function degreesSum

degreesSum(start: number, amount: number, clockwise?: boolean): number
Sum angles together, accounting for the 'wrap around'.

clockwise of true (default) means angles are added in clockwise direction
```
// From 180deg, add 90deg in the clockwise direction
radiansSum(180, 90, true);
```
radiansSum is the same, but uses radians (0..2 Pi)

Orientation of angles is as follows:
```
      90
       |
180 ---+--- 0
       |
      270
```
Parameters
- start: number
  Starting angle, in degrees
- amount: number
  Angle to add, in degrees
- clockwise: boolean = true
  Add in clockwise direction (default: true)
Returns number
Sum result, in degrees