Ability to specify specific udp port usage for live view
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# Feature Request

### Description
If operating homebridge-ring in a segregated network, it seems almost impossible for live view to work due to a huge range of ports that need to be opened in both directions.

### Describe the solution you'd like
Either publish the port range that is used for the live view RTSP connection - or provide the ability to limit the number of ports down to a reasonable number

### Describe alternatives you've considered
Workaround is currently to open a significant number of ports (or even all ports between clients and the homebridge server)