Update dependencies to enable Greenkeeper 🌴 (#2)

* chore(package): update dependencies

* docs(readme): add Greenkeeper badge

README.md

@@ -1,5 +1,7 @@
 # create-test-server
 
+[![Greenkeeper badge](https://badges.greenkeeper.io/lukechilds/create-test-server.svg)](https://greenkeeper.io/)
+
 > Creates a minimal express server for testing
 
 [![Build Status](https://travis-ci.org/lukechilds/create-test-server.svg?branch=master)](https://travis-ci.org/lukechilds/create-test-server)

package.json

@@ -44,7 +44,7 @@
     "coveralls": "^2.13.1",
     "eslint-config-xo-lukechilds": "^1.0.0",
     "got": "^7.0.0",
-    "nyc": "^10.3.2",
+    "nyc": "^11.0.2",
     "xo": "^0.19.0"
   }
 }