function inspect(obj, showHidden, depth, colors) {
      var ctx = {
        showHidden: showHidden,
        seen: [],
        stylize: function (str) { return str; }
      };
      return formatValue(ctx, obj, (typeof depth === 'undefined' ? 2 : depth));
    }
Echos the value of a value. Trys to print the value out
in the best way possible given the different types.

@param {Object} obj The object to print out.
@param {Boolean} showHidden Flag that shows hidden (not enumerable)
   properties of objects.
@param {Number} depth Depth in which to descend in object. Default is 2.
@param {Boolean} colors Flag to turn on ANSI escape codes to color the
   output. Default is false (no coloring).