- npm: Update devDep Rollup

- Linting (ESLint): Prefer `const` over `let`
- Build: Update `dist` files

package.json

@@ -67,7 +67,7 @@
     "node-static": "^0.7.10",
     "opn-cli": "^3.1.0",
     "qunit": "^2.6.1",
-    "rollup": "0.59.4",
+    "rollup": "0.60.0",
     "rollup-plugin-babel": "^3.0.4",
     "rollup-plugin-commonjs": "^9.1.3",
     "rollup-plugin-json": "^3.0.0",