- Linting (ESLint): Remove now unneeded config and add per new update

- Refactoring: Prefer for-of, event.key (newly enforced linting)
- Refactoring: Better var. names
- npm: Update devDeps and update local copies

dist/extensions/ext-server_opensave.js

@@ -924,7 +924,7 @@ var svgEditorExtension_server_opensave = (function () {
   * @param {HTMLCanvasElement|string} target canvas element or the id of a canvas element
   * @param {string|XMLDocument} s - svg string, url to svg file, or xml document
   * @param {module:canvg.CanvgOptions} [opts] Optional hash of options
-  * @returns {Promise} All the function after the first render is completed with dom
+  * @returns {Promise<XMLDocument|XMLDocument[]>} All the function after the first render is completed with dom
   */