Add documentation for Somfy MyLink platform (#9063)

* Added documentation page

* Updated HA Category metadata

Co-Authored-By: bendews <contact@bendews.com>

* Removed `redirect_from` as not required

* Removed ‘Scene’ functionality

* Added IP address placeholder

Co-Authored-By: bendews <contact@bendews.com>

* Added IP & System ID placeholders

* Fixed typo (“SYSTEM_ID” placeholder instead of “MYLINK_ID”)

* Removed references to ‘Scenes’ in documentation

* Added default values for boolean config options

* Updated phrasing

source/_components/somfy_mylink.markdown

@@ -0,0 +1,69 @@
+---
+layout: page
+title: "Somfy MyLink"
+description: "Instructions on how to integrate Somfy MyLink devices with Home Assistant."
+date: 2019-03-29 12:00
+sidebar: true
+comments: false
+sharing: true
+footer: true
+logo: tahoma.png
+ha_category:
+  - Hub
+  - Cover
+ha_release: 0.92
+ha_iot_class: "Assumed State"
+---
+
+The `Somfy MyLink` integration is used as an interface to a compatible Somfy MyLink hub utilizing the `Synergy` API. It allows the addition of covers from the Somfy MyLink platform to Home Assistant.
+
+To use your compatible `Somfy MyLink` devices in your installation, add the following to your `configuration.yaml` file:
+
+```yaml
+# Example configuration.yaml entry
+somfy_mylink:
+  host: IP_ADDRESS
+  system_id: SYSTEM_ID
+```
+
+{% configuration %}
+host:
+  description: The IP address of the Somfy MyLink hub device.
+  required: true
+  type: string
+system_id:
+  description: The `System ID` of the Somfy MyLink hub. This can be found in the `Integration` menu in the mobile app.
+  required: true
+  type: string
+default_reverse:
+  description: Sets the default reversal status of the cover. Possible values are `true` or `false`. This value can be applied on a per-cover basis (see `entity_config` below)
+  required: false
+  type: boolean
+  default: false
+entity_config:
+  description: Configuration for specific cover entities. All subordinate keys are the corresponding entity ids to the domains, e.g., `cover.bedroom_blinds`.
+  required: false
+  type: map
+  keys:
+    '`<ENTITY_ID>`':
+      description: Additional options for specific entities.
+      required: false
+      type: map
+      keys:
+        reverse:
+          description: Reverses the direction of the cover. Possible values are `true` or `false`.
+          required: false
+          type: boolean
+          default: false
+{% endconfiguration %}
+
+```yaml
+# Advanced configuration.yaml entry setting specific options on a per-cover basis
+somfy_mylink:
+  host: IP_ADDRESS
+  system_id: SYSTEM_ID
+  default_reverse: true
+  entity_config:
+    cover.outdoor_awning:
+        reverse: false
+```