Add saj component to docs (#10455)

* Add saj component to docs

* Adjust example + remove redirect_from

* Update doc according to requested component change

source/_components/saj.markdown

@@ -0,0 +1,47 @@
+---
+title: "SAJ Solar Inverter"
+description: "Instructions on how to connect your SAJ Solar Inverter to Home Assistant."
+ha_category:
+  - Energy
+logo: saj.png
+ha_iot_class: Local Polling
+ha_release: "0.100"
+---
+
+The `saj` sensor will poll a [SAJ](https://www.saj-electric.com/) solar inverter and present the values as sensors in Home Assistant.
+
+This sensor uses the web interface and to use it, you have to be able to connect to the solar inverter from your favorite web browser.
+
+## Configuration
+
+To enable this sensor, add the following lines to your `configuration.yaml` file:
+
+```yaml
+# Example configuration.yaml entry
+sensor:
+  - platform: saj
+    host: IP_ADDRESS_OF_DEVICE
+```
+
+{% configuration %}
+host:
+  description: The IP address of the SAJ Solar Inverter.
+  required: true
+  type: string
+{% endconfiguration %}
+
+## Sensors
+
+Sensors available in the library:
+
+| name               | Unit | Description                                |
+|--------------------|------|:-------------------------------------------|
+| current_power      | W    | Current power generated by the inverter.   |
+| today_yield        | kWh  | Power yield for today.                     |
+| today_time         | h    | Inverter's running time for today.         |
+| today_max_current  | W    | Maximum current power for today.           |
+| total_yield        | kWh  | Total kWh generated to date.               |
+| total_time         | h    | Total running time of the inverter .       |
+| total_co2_reduced  | kg   | Total CO2 in kg reduced.                   |
+| temperature        | °C   | Temperature of the inverter.               |
+| state              | N/A  | Live state of the inverter.                |