Update README.md

The project lacked proper README.md documentation. I added a better
description of the module, usage and configuration information, as well
as info about issues and pull requests, and the license.

README.md

@@ -1,2 +1,59 @@
-# ghost-slack-integration
-Super simple Ghost blog Slack-integration to notify Slack channel upon new posts.
+# rss-slack-integration
+This module implements a super simple rss feed Slack integration that posts a
+notification to a Slack group channel when new posts are added to the feed.
+
+The module is a thin wrapper around the excellent
+[rss-watcher module](https://www.npmjs.com/package/rss-watcher). It essentially
+uses the rss-watcher's `new article` event to fetch the article title and url,
+and does a post request to a given Slack group's incoming web hook URL with a
+message consisting of the article title and url.
+
+## Installation
+
+Simply install in project using `npm install --save rss-slack-integration`.
+
+
+## Usage and Configuration
+
+The module is very simple. It exposes a single function `start` which expects a
+configuration object as its sole parameter.
+
+Example usage:
+
+```JavaScript
+var rsi = require("rss-slack-integration");
+
+rsi.start({
+  feed: "https://example.com/rss",
+  interval: 60,
+  slackHook: "https://hooks.slack.com/services/yourservicehash",
+  slackIcon: "https://example.com/icon.png",
+  slackBotUser: "Bot Username"})
+```
+The `feed` property should be the URL of the rss feed you want to receive
+updates about. Take care to provide the protocol part of the URL. The `interval`
+property specifies the number of seconds between each poll of the rss feed.
+Setting this to `60` means that the `rss-watcher` module will poll the
+rss-feed for changes once a minute.
+
+The `slackHook` property should be set to whatever URL was generated by Slack
+when you created the
+[incoming webhook](https://api.slack.com/incoming-webhooks). The `slackIcon`
+property should be set to the URL of the icon you want to use for the Slack
+bot. The last property, `slackBotUser` should be set to whatever bot name you
+want your Slack web hook messages to appear under, for example the name of the
+rss feed's site.
+
+## Issues and contributions
+
+If you experience any issues with this module you can submit issues at the
+[project's Github Repository](https://github.com/pilsprog/rss-slack-integration/issues).
+
+Any help towards improving this module is welcome. If you want to add features
+or fix bugs you are welcome to submit a
+[pull request](https://github.com/pilsprog/rss-slack-integration/pulls).
+
+## License
+
+This project is licensed under MIT. See the
+[LICENSE file](https://github.com/pilsprog/rss-slack-integration/blob/master/LICENSE).