Update dependencies

package.json

@@ -32,20 +32,20 @@
     "./lib/random/random-byte.js": "./lib/random/random-byte-browser.js"
   },
   "devDependencies": {
-    "chai": "^3.3.0",
-    "envify": "^3.4.0",
-    "grunt": "^0.4.5",
-    "grunt-browserify": "^3.6.0",
-    "grunt-cli": "^0.1.13",
-    "grunt-contrib-concat": "^0.5.1",
-    "grunt-contrib-jshint": "^0.11.3",
-    "grunt-contrib-uglify": "^0.9.2",
-    "grunt-mocha-test": "^0.12.7",
+    "chai": "^4.1.2",
+    "envify": "^4.1.0",
+    "grunt": "^1.0.3",
+    "grunt-browserify": "^5.3.0",
+    "grunt-cli": "^1.2.0",
+    "grunt-contrib-concat": "^1.0.1",
+    "grunt-contrib-jshint": "^1.1.0",
+    "grunt-contrib-uglify": "^3.3.0",
+    "grunt-mocha-test": "^0.13.3",
     "grunt-notify": "^0.4.1",
     "grunt-open": "^0.2.3",
-    "grunt-release": "^0.13.0",
-    "load-grunt-tasks": "^3.3.0",
-    "mocha": "^2.3.3",
+    "grunt-release": "^0.14.0",
+    "load-grunt-tasks": "^4.0.0",
+    "mocha": "^5.2.0",
     "time-grunt": "^1.2.1"
   },
   "license": "MIT",