sjl.js
function wrapPointer (pointer, min, max) {
        return pointer > max ? min : (pointer < min ? max : pointer);
    }
function wrapPointer (pointer, min, max) {
        return pointer > max ? min : (pointer < min ? max : pointer);
    }
Wraps a pointer (number) around a bounds (range of two numbers) or returns the next valid pointer depending
on direction:  E.g.,
If pointer is less than `min` then returns `max`.  If pointer is greater than `max` returns `min`.
If pointer is within bounds then returns `pointer`.
@function module:sjl.wrapPointer
@param pointer {Number}
@param min {Number}
@param max {Number}
@returns {Number}