fix(package): make nuxt devDependency

needed for nuxt-start

Author: Pooya Parsa

package.json

@@ -31,10 +31,10 @@
     "axios": "^0.16.2",
     "chalk": "^2.1.0",
     "debug": "^3.0.1",
-    "nuxt": "^1.0.0-rc8",
     "whatwg-url": "^6.1.0"
   },
   "devDependencies": {
+    "nuxt": "^1.0.0-rc8",
     "codecov": "^2.3.0",
     "eslint": "^4.5.0",
     "eslint-config-standard": "^10.2.1",