Method deleteSubPanel

js/Sign.js:179–181

* Deletes a subpanel * @param {number} subPanelIndex - you already know lol

(subPanelIndex)

    */
    
    deleteSubPanel(subPanelIndex) {
        this.subPanels.splice(subPanelIndex, 1);
    }
	
	duplicateSubPanel(subPanelIndex) {
		const existingSubPanel = this.subPanels[subPanelIndex];