Initializes the global QuickTips instance and prepare any quick tips.
@param {Boolean} [autoRender=true] True to render the QuickTips container
immediately to preload images.
@param {Object} [config] config object for the created QuickTip. By
default, the {@link Ext.tip.QuickTip QuickTip} class is instantiated, but this can
be changed by supplying an xtype property or a className property in this object.
All other properties on this object are configuration for the created component.
function (autoRender, config) {
            if (!tip) {
                if (!Ext.isReady) {
                    Ext.onReady(function(){
                        Ext.tip.QuickTipManager.init(autoRender, config);
                    });
                    return;
                }

                var tipConfig = Ext.apply({ disabled: disabled, id: 'ext-quicktips-tip' }, config),
                    className = tipConfig.className,
                    xtype = tipConfig.xtype;

                if (className) {
                    delete tipConfig.className;
                } else if (xtype) {
                    className = 'widget.' + xtype;
                    delete tipConfig.xtype;
                }

                if (autoRender !== false) {
                    tipConfig.renderTo = document.body;

                    //<debug>
                    if (tipConfig.renderTo.tagName.toUpperCase() != 'BODY') { // e.g., == 'FRAMESET'
                        Ext.Error.raise({
                            sourceClass: 'Ext.tip.QuickTipManager',
                            sourceMethod: 'init',
                            msg: 'Cannot init QuickTipManager: no document body'
                        });
                    }
                    //</debug>
                }

                tip = Ext.create(className || 'Ext.tip.QuickTip', tipConfig);

                // private.
                // Need a globally accessble way of testing whether QuickTipsManager is both loaded AND initialized.
                Ext.quickTipsActive = true;
            }
        }