Description: these are optional modules

--- a/package.json
+++ b/package.json
@@ -36,14 +36,8 @@
     "coveralls": "^3.0.0",
     "es6-promise": "^4.2.4",
     "grunt": "^1.0.2",
-    "grunt-banner": "^0.6.0",
     "grunt-cli": "^1.2.0",
     "grunt-contrib-clean": "^1.1.0",
-    "grunt-contrib-watch": "^1.0.0",
-    "grunt-eslint": "^20.1.0",
-    "grunt-karma": "^2.0.0",
-    "grunt-mocha-test": "^0.13.3",
-    "grunt-ts": "^6.0.0-beta.19",
     "grunt-webpack": "^1.0.18",
     "istanbul-instrumenter-loader": "^1.0.0",
     "jasmine-core": "^2.4.1",