Added documentation for Flume integration (#10624)

* Added documentation for Flume integration

* ✏️ Tweak

* Update source/_integrations/flume.markdown

Co-Authored-By: Klaas Schoute <klaas_schoute@hotmail.com>

* Update flume.markdown

Removed reference to Device ID, as this is no longer required.

* Update flume.markdown

Removed time zone requirements. This now uses the default Time Zone specified in HASS configuration.

* ✏️ Tweaks

* ✏️ Tweak

* ✏️ Typo in YAML


Co-authored-by: Klaas Schoute <klaas_schoute@hotmail.com>
Co-authored-by: Franck Nijhof <frenck@frenck.nl>

source/_integrations/flume.markdown

@@ -0,0 +1,72 @@
+---
+title: "flume"
+description: "Documentation about the flume sensor."
+ha_category:
+  - Sensor
+ha_iot_class: Cloud Polling
+ha_release: 0.103
+---
+
+The `flume` sensor will show you the current [flume](https://portal.flumetech.com/) status for the given Device ID.
+
+Flume monitors the real-time status of your home water meter. Allowing the end-user to detect small leaks, gain real-time information on household water consumption, set water goals and budgets, and receive push notifications when suspicious water activities occur. 
+
+## Configuration
+
+You can find your Client ID and Client Secret under "API Access" on the [settings page](https://https://portal.flumetech.com/#settings). 
+
+To enable the flume sensor, add the following lines to your `configuration.yaml` file:
+
+```yaml
+# Example configuration.yaml entry
+sensor:
+  # Flume
+  - platform: flume
+    username: YOUR_FLUME_USERNAME
+    password: YOUR_FLUME_PASSWORD
+    client_id: YOUR_FLUME_CLIENT_ID
+    client_secret: YOUR_FLUME_CLIENT_SECRET
+```
+
+{% configuration %}
+username:
+  description: Your flume user id.
+  required: true
+  type: string
+password:
+  description: Your flume password.
+  required: true
+  type: string
+client_id:
+  description: Your flume Client ID.
+  required: true
+  type: string
+client_secret:
+  description: Your flume Client Secret.
+  required: true
+  type: string
+name:
+  description: A name to display on the sensor.
+  required: false
+  default: Flume Sensor
+  type: string
+{% endconfiguration %}
+
+# Configuration for Binary Sensor
+
+The following YAML creates a binary sensor. This requires the default sensor to be configured successfully.
+
+{% raw %}
+
+```yaml
+# Example configuration.yaml entry
+binary_sensor:
+  - platform: template
+    sensors:
+      flume_status:
+        friendly_name: "Flume Flow Status"
+        value_template: >-
+          {{ states.sensor.flume_sensor.state != "0" }}
+```
+
+{% endraw %}