Update dependencies to enable Greenkeeper 🌴 (#877)

* chore(package): update dependencies
* docs(readme): add Greenkeeper badge

README.md

 # converse.js
 
+[![Greenkeeper badge](https://badges.greenkeeper.io/jcbrand/converse.js.svg)](https://greenkeeper.io/)
+
 [![Travis](https://api.travis-ci.org/jcbrand/converse.js.png?branch=master)](https://travis-ci.org/jcbrand/converse.js)
 [![Bountysource bounties](https://img.shields.io/bountysource/team/converse.js/activity.svg?maxAge=2592000)](https://www.bountysource.com/teams/converse.js/issues?tracker_ids=194169)
 [![Translation status](https://hosted.weblate.org/widgets/conversejs/-/svg-badge.svg)](https://hosted.weblate.org/engage/conversejs/?utm_source=widget)

package.json

@@ -49,9 +49,9 @@
     "font-awesome": "^4.7.0",
     "greenkeeper": "^4.2.1",
     "http-server": "^0.10.0",
-    "install": "^0.8.5",
+    "install": "^0.9.5",
+    "jed": "1.1.1",
     "jasmine-core": "2.6.4",
-    "jed": "0.5.4",
     "jquery": "3.2.1",
     "jshint": "^2.9.4",
     "lodash": "4.17.4",