Amcrest IP2M-842E POE bullet camera configuration tested and working

Manufacturer/Model: Amcrest IP2M-842E POE outdoor bullet camera

Homebridge Config:

"name": "Camera FFmpeg",
"cameras": [
  {
    "name": "Outdoor Camera",
    "manufacturer": "Amcrest",
    "model": "IP2M-842E",
    "serialNumber": "XXXXXXXXXXXXXX",
    "firmwareRevision": "2.520.0000.0.R",
    "videoConfig": {
      "source": "-rtsp_transport tcp -re -i rtsp://username:password@ipaddress:554/cam/realmonitor?channel=1&subtype=0",
      "stillImageSource": "-i http://username:password@ipaddress/cgi-bin/snapshot.cgi?chn=1",
      "maxStreams": 2,
      "maxWidth": 1920,
      "maxHeight": 1080,
      "maxFPS": 30,
      "maxBitrate": 2048,
      "vcodec": "libx264 -preset ultrafast",
      "audio": false
    }
  }
]

Additional Information:

Based on the Amcrest IP4M-1026 configuration, slightly modified for this specific camera.
The streaming appears to be working on iOS 14.1 and tvOS 14.3.
Works on a headless Ubuntu server with those specs, but may want to dial the values down to make it work on a Raspberry Pi e.g.:
```
"maxWidth": 1280,
"maxHeight": 720,
"maxFPS": 15,
"maxBitrate": 1024,
```

homebridge-plugins / homebridge-camera-ffmpeg

Amcrest IP2M-842E POE bullet camera configuration tested and working #919