Update dev dependencies (#229)

Author: crwhite21

package.json

@@ -41,11 +41,11 @@
     "typescript": "1.8.10"
   },
   "devDependencies": {
-    "grunt": "^0.4.5",
+    "grunt": "^1.0.1",
     "grunt-cli": "^1.2.0",
-    "grunt-contrib-clean": "^0.7.0",
-    "grunt-contrib-watch": "~0.6.1",
-    "grunt-mocha-istanbul": "^3.0.1",
+    "grunt-contrib-clean": "^1.0.0",
+    "grunt-contrib-watch": "^1.0.0",
+    "grunt-mocha-istanbul": "^5.0.1",
     "grunt-string-replace": "^1.2.0",
     "grunt-ts": "^5.3.0-beta.2",
     "istanbul": "^0.4.1",