code: function (x, y) {
              var a = this.val;
  
              a[6] += a[0] * x + a[3] * y;
              a[7] += a[1] * x + a[4] * y;
  
              return this;
          }
docs: translate the matrix position on the horizontal and vertical axis
  @name translate
  @memberOf me.Matrix2d
  @function
  @param {Number} x the x coordindates to translate the matrix by
  @param {Number} y the y coordindates to translate the matrix by
  @return {me.Matrix2d} Reference to this object for method chaining