Create sensor.rtorrent.markdown (#6780)

* Create sensor.rtorrent.markdown

* Add unofficial rtorrent logo

rtorrent doesn't have an official logo, but this one is the most widely used.

* Add logo and remove additional empty lines

* Set ha_release to 0.80

* Updated description and configuration tags

* Put descriptions first in configuration section

* Update sensor.rtorrent.markdown

source/_components/sensor.rtorrent.markdown

@@ -0,0 +1,57 @@
+---
+layout: page
+title: "rtorrent Sensor"
+description: "Instructions on how to integrate rtorrent sensors within Home Assistant."
+date: 2018-10-14 05:40
+sidebar: true
+comments: false
+sharing: true
+footer: true
+logo: rtorrent.png
+ha_category: Downloading
+ha_release: 0.81
+ha_iot_class: "Local Polling"
+---
+
+The `rtorrent` platform allows you to monitor your downloads with [rtorrent](https://rakshasa.github.io/rtorrent/) from within Home Assistant and setup automations based on the information.
+
+To enable this sensor, add the following lines to your `configuration.yaml`:
+
+```yaml
+# Example configuration.yaml entry
+sensor:
+  - platform: rtorrent
+    url: 'http://<user>:<password>@<host>:<port>/RPC2'
+    monitored_variables:
+      - 'current_status'
+      - 'download_speed'
+      - 'upload_speed'
+```
+
+This sensor requires the rtorrent XMLRPC API exposed on an HTTP interface.
+Note that for security reasons, simply using the SCGI interface (default `localhost:5000`) of rtorrent won't work.
+The [official reference](https://github.com/rakshasa/rtorrent/wiki/RPC-Setup-XMLRPC) describes how to set up that HTTP interface.
+
+Alternatively, the [arch-rtorrentvpn](https://github.com/binhex/arch-rtorrentvpn) container can be used with `url` set to `http://admin:rutorrent@127.0.0.1:9080/RPC2`.
+
+{% configuration %}
+url:
+  description: The URL to the HTTP endpoint of the rtorrent XMLRPC API.
+  required: true
+  type: string
+name:
+  description: The name to use when displaying this rtorrent instance.
+  required: false
+  type: string
+monitored_variables:
+  description: Conditions to be monitored.
+  required: true
+  type: list
+  keys:
+    current_status:
+      description: The status of your rtorrent daemon.
+    download_speed:
+      description: The current download speed.
+    upload_speed:
+      description: The current upload speed.
+{% endconfiguration %}