static round(value, decimals) {
    decimals = decimals ? decimals : 1;
    return Number(Math.round(value + 'e' + decimals) + 'e-' + decimals);
  }
Rounds a value to a given number of decimals.

@static
@param {Number} value A number.
@param {Number} decimals The number of decimals.
@returns {Number} A number rounded to a given number of decimals.