- npm: Update devDeps

- Build: Switch to `terser` plugin with `uglify` plugin not
    supporting ES6+-capable minifier
- Linting (ESLint): Consistent curly spacing; follow new "standard"

test/path_test.js

@@ -1,4 +1,5 @@
 /* eslint-env qunit */
+/* globals SVGPathSeg */
 import '../editor/svgpathseg.js';
 import {NS} from '../editor/namespaces.js';
 import * as utilities from '../editor/utilities.js';