code: function max (o, func) {
                      if(!o || typeof o !== 'object') return o;
                      if(libs.object.size(o) === 0) return;
  
                      if(!(func instanceof Function)) func = undefined;
                      var max, maxValue;
  
                      if(!func) {
                          max = libs.object.first(o);
                          libs.object.each(o, 1, function (item) {
                              if(item >= max) max = item;
                          });
                      }
                      else {
                          max      = libs.object.first(o);
                          maxValue = func.call(max, max);
  
                          libs.object.each(o, 1, function (item) {
                              var value = func.call(item, item);
                              if(value >= maxValue) {
                                  max      = item;
                                  maxValue = value;
                              }
                          });
                      }
                      return max;
                  }
docs: Returns the maximum item in the object.
  @param {Object} o The object to operate on.
  @param {Function=} func If passed, the function will be invoked for each item in the object collection.
  @return {*} The maximum item in the object collection.