scale = (out, vector, amount) => {
  out[0] = vector[0] * amount
  out[1] = vector[1] * amount
  return out
}
Scales the coordinates of the given vector.

@param {vec2} out - receiving vector
@param {vec2} vector - vector to scale
@param {Number} amount - amount to scale
@returns {vec2} out
@alias module:modeling/maths/vec2.scale