Updated dev dependencies

Author: jouni-kantola

package.json

@@ -21,13 +21,13 @@
     "src"
   ],
   "devDependencies": {
-    "ava": "^0.19.1",
-    "eslint": "^3.19.0",
-    "eslint-plugin-prettier": "^2.0.1",
-    "husky": "^0.13.3",
-    "lint-staged": "^3.4.0",
-    "nyc": "^10.2.0",
-    "prettier": "^1.1.0"
+    "ava": "^0.23.0",
+    "eslint": "^4.9.0",
+    "eslint-plugin-prettier": "^2.3.1",
+    "husky": "^0.14.3",
+    "lint-staged": "^4.3.0",
+    "nyc": "^11.2.1",
+    "prettier": "^1.7.4"
   },
   "dependencies": {
     "webpack-sources": "^1.0.1"