Function everyNth

everyNth<T>(nth: number, callback?: (data: T) => void): (data: T) => boolean
Returns true for every _n_th call, eg 2 for every second call.

If nth is 1, returns true for everything. 0 will be false for everything.

Usage:
```
const tenth = everyNth(10);
window.addEventListener(`pointermove`, evt => {
 if (!tenth(evt)) return; // Filter out
 // Continue processing, it is the 10th thing.

});
```
Alternative:
```
window.addEventListener(`pointermove`, everyNth(10, evt => {
 // Do something with tenth item...
});
```
Type Parameters
- T
Parameters
- nth: number
  Every nth item
- Optionalcallback: (data: T) => void
Returns (data: T) => boolean
Function which in turn returns true if nth call has been hit, false otherwise