code: function _initialLayout(forceRefresh) {
          var panes = Object.keys(_panes),
              size = 100 / panes.length;
  
          _.forEach(_panes, function (pane) {
              if (pane.id === FIRST_PANE) {
                  if (_orientation === VERTICAL) {
                      pane.$el.css({height: "100%",
                                    width: size + "%",
                                    float: "left"
                                   });
                  } else {
                      pane.$el.css({ height: size + "%",
                                     width: "100%"
                                   });
                  }
              } else {
                  if (_orientation === VERTICAL) {
                      pane.$el.css({  height: "100%",
                                      width: "auto",
                                      float: "none"
                                   });
                  } else {
                      pane.$el.css({ width: "100%",
                                     height: "50%"
                                   });
                  }
              }
  
              _synchronizePaneSize(pane, forceRefresh);
          });
      }
docs: Sets up the initial layout so panes are evenly distributed
  This also sets css properties that aid in the layout when _updateLayout is called
  @param {boolean} forceRefresh - true to force a resize and refresh of the entire view
  @private