function isValidPrecisionValue(value) {
			return (typeof (value) === 'number') && !isNaN(value) && value >= 0 && value <= 20;
		}
Calculates next/previous value that is fold by the provided step
@param {number} fValue the base value
@param {number} step the step to increase the value to
@param {number} iSign direction, where if 1 -> increase, -1-> decrease.
@returns {number} the next/previous value.
@private