"Productionizing" WebRTC functionality

[cwisniew]

Is your feature request related to a problem? Please describe.
After the pilot/beta phase of WebRTC "productionalize" (yes I am aware this is not a real word) the feature.

Additional Context
Based on feedback and testing experience with the pilot/beta make any changes that are required to make this more robust.

Depends on RPTools/maptool-server-registry#9

[thelsing]

Additional TODO:

• Check that all user displayed strings are localized.
• Check behavior if server with same name exists. Will be handled in [Refactoring]: Server initialization #3790
• Check behavior if player with same name exists on same server. Will be handled in [Refactoring]: Server initialization #3790
• Check switching roles between client and server without restarting MT.
• Move WebRtc bool to ServerConfig. (As server type enum in case we have more Connections types in the future.)

[thelsing]

Issues are handled in #3789 . Issues if server or player already exists are not specific to webrtc only easier to produce. I created #3790 for them.