Update all node_modules to newest versions

package.json

@@ -28,18 +28,18 @@
     "test": "karma start --log-level debug --single-run=true"
   },
   "devDependencies": {
-    "eslint": "^5.15.3",
+    "eslint": "^6.8.0",
     "jscs": "^3.0.7",
-    "jshint": "^2.10.2",
-    "karma": "^4.0.0",
-    "karma-chrome-launcher": "^2.2.0",
-    "karma-firefox-launcher": "^1.1.0",
-    "karma-qunit": "^2.1.0",
+    "jshint": "^2.11.0",
+    "karma": "^4.4.1",
+    "karma-chrome-launcher": "^3.1.0",
+    "karma-firefox-launcher": "^1.3.0",
+    "karma-qunit": "^4.0.0",
     "ls": "^0.2.1",
-    "puppeteer": "^1.13.0",
-    "qunit": "^2.9.2",
-    "syn": "^0.13.0",
-    "terser": "^3.17.0"
+    "puppeteer": "^2.1.1",
+    "qunit": "^2.9.3",
+    "syn": "^0.14.1",
+    "terser": "^4.6.7"
   },
   "dependencies": {}
 }