function createBottomPanel(id, $panel, minSize) {
        $panel.insertBefore("#status-bar");
        $panel.hide();
        updateResizeLimits();  // initialize panel's max size

        panelIDMap[id] = new Panel($panel, minSize);
        panelIDMap[id].panelID = id;

        return panelIDMap[id];
    }
Creates a new resizable panel beneath the editor area and above the status bar footer. Panel is initially invisible.
The panel's size & visibility are automatically saved & restored as a view-state preference.

@param {!string} id  Unique id for this panel. Use package-style naming, e.g. "myextension.feature.panelname"
@param {!jQueryObject} $panel  DOM content to use as the panel. Need not be in the document yet. Must have an id
     attribute, for use as a preferences key.
@param {number=} minSize  Minimum height of panel in px.
@return {!Panel}