Add Camera to Alexa Smart Home (#12519)

* Update Alexa Smart Home to include Camera configuration.

* ✏️ Tweak

Co-authored-by: Franck Nijhof <frenck@frenck.nl>

source/_integrations/alexa.smart_home.markdown

@@ -412,6 +412,7 @@ The following integrations are currently supported:
 - [Binary Sensor](#binary-sensor)
   - [Doorbell Announcement](#doorbell-announcement)
   - [Presence Detection](#presence-detection-with-binary-sensor)
+- [Camera](#camera)
 - [Climate](#climate)
 - [Cover](#cover)
   - [Garage Doors](#garage-doors)
@@ -569,6 +570,18 @@ Each Echo device will need the communication and Announcements setting enabled,
 
 [Image Processing](#image-processing) entities also support this notification.
 
+### Camera
+
+View a camera stream on an Amazon echo device.
+
+- _"Alexa, show the front door camera."_
+
+The [`stream`](/integrations/stream/) integration is required to stream cameras to Amazon echo devices.
+
+The Amazon echo device will request the camera stream from Home Assistant. The Home Assistant URL must be accessible from the network the Amazon echo device is connected to and must support HTTPS on port 443 with a certificate signed by [an Amazon approved certificate authority](https://ccadb-public.secure.force.com/mozilla/IncludedCACertificateReport). These requirements can be satisfied with with Home Assistant Cloud, or LetsEncrypt/DuckDNS.
+
+Enable preload stream option for cameras used with echo devices to reduce response time, and prevent timing out before the 6 second limit.   
+
 ### Climate
 
 Single, double, and triple set-point thermostats are supported. The temperature value from the thermostat will also be exposed at a separate [temperature sensor](#sensor).