Allow cameras to be disabled in config (#4162)

* add option enabled for each camera in config

* Simplified If-block and removed wrong Optional

* Update Docs enabling/disabling camera in config

* correct format for option

* Disabling Camera for processes, no config changes

* Describe effects of disabled cam in documentation

* change if-logic, obsolete copy, info disabled cam

* changed color to white, added top padding in disabled camera info

* changed indentation

docs/docs/configuration/cameras.md

@@ -7,6 +7,8 @@ title: Cameras
 
 Several inputs can be configured for each camera and the role of each input can be mixed and matched based on your needs. This allows you to use a lower resolution stream for object detection, but create recordings from a higher resolution stream, or vice versa.
 
+A camera is enabled by default but can be temporarily disabled by using `enabled: False`. Existing events and recordings can still be accessed. Live streams, recording and detecting are not working. Camera specific configurations will be used.
+
 Each role can only be assigned to one input per camera. The options for roles are as follows:
 
 | Role       | Description                                                                                          |
@@ -21,6 +23,7 @@ mqtt:
   host: mqtt.server.com
 cameras:
   back:
+    enabled: True
     ffmpeg:
       inputs:
         - path: rtsp://viewer:{FRIGATE_RTSP_PASSWORD}@10.0.10.10:554/cam/realmonitor?channel=1&subtype=2
@@ -45,4 +48,4 @@ cameras:
   side: ...
 ```
 
-For camera model specific settings check the [camera specific](/configuration/camera_specific) infos.
+For camera model specific settings check the [camera specific](/configuration/camera_specific) infos.