Absolute mode: editor is not defined

Hi,

Great project, thanks! In relation to issue #1936 there is a bug on the following line which causes exceptions when attempting to drag an absolute component when the variable editor is not defined in the window scope, for example, if you have instantiated the editor inside a React class, or not used the name editor.

https://github.com/artf/grapesjs/blob/1ebcf47d4ad3c9e7cdc8196a1c10043157fe6a64/src/commands/index.js#L153-L155

I believe the correct implementation for this would be the following, where ed is passed into the tlb-move run function. https://github.com/artf/grapesjs/blob/1ebcf47d4ad3c9e7cdc8196a1c10043157fe6a64/src/commands/index.js#L120-L121

            dragger = ed.runCommand('core:component-drag', {

This can be reproduced on jsfiddle by changing editor to e, thus taking it out of window scope. https://jsfiddle.net/xd4j6vwa/2/

Workaround Set editor in the window scope, for example window.editor = this.editor;