Update dependencies to enable Greenkeeper 🌴 (#25)

* chore(package): update dependencies

* chore(travis): whitelist greenkeeper branches

* docs(readme): add Greenkeeper badge

* chore(package): Upgrade dependencies

.travis.yml

@@ -21,6 +21,7 @@ env:
 branches:
   only:
     - master
+    - /^greenkeeper/.*$/
 
 cache:
   directories:

readme.md

@@ -1,6 +1,6 @@
 # Coldbox v1.7.0
 
-[![Build Status](https://travis-ci.org/mirucon/coldbox.svg?branch=master)](https://travis-ci.org/mirucon/coldbox) [![FOSSA Status](https://app.fossa.io/api/projects/git%2Bgithub.com%2Fmirucon%2Fcoldbox.svg?type=shield)](https://app.fossa.io/projects/git%2Bgithub.com%2Fmirucon%2Fcoldbox?ref=badge_shield) [![License: GPL v2](https://img.shields.io/badge/License-GPL%20v2-blue.svg)](https://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html)
+[![Build Status](https://travis-ci.org/mirucon/coldbox.svg?branch=master)](https://travis-ci.org/mirucon/coldbox) [![FOSSA Status](https://app.fossa.io/api/projects/git%2Bgithub.com%2Fmirucon%2Fcoldbox.svg?type=shield)](https://app.fossa.io/projects/git%2Bgithub.com%2Fmirucon%2Fcoldbox?ref=badge_shield) [![License: GPL v2](https://img.shields.io/badge/License-GPL%20v2-blue.svg)](https://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html) [![Greenkeeper badge](https://badges.greenkeeper.io/mirucon/coldbox.svg)](https://greenkeeper.io/)
 
 ![coldbox-screenshot](/screenshot.jpg)