update development dependencies

Author: Qix-

package.json

@@ -44,12 +44,12 @@
     "@babel/cli": "^7.0.0",
     "@babel/core": "^7.0.0",
     "@babel/preset-env": "^7.0.0",
-    "browserify": "14.4.0",
-    "chai": "^3.5.0",
-    "concurrently": "^3.1.0",
+    "browserify": "16.2.3",
+    "chai": "^4.2.0",
+    "concurrently": "^4.1.0",
     "coveralls": "^3.0.2",
     "istanbul": "^0.4.5",
-    "karma": "^2.0.0",
+    "karma": "^3.1.4",
     "karma-chai": "^0.1.0",
     "karma-mocha": "^1.3.0",
     "karma-chrome-launcher": "^2.2.0",