New PvP gamemode: "Tactical TDM"

[Jano Msik]

When normal TDM or Slaughter ends and weaker team doesn't have any respawn points anymore, the player behavior suddenly change from "rush kamikadze" to far more tactical.

Hence I propose a gamemode which would mix features of existing Artifact and TDM to capitalize on this and bring new dynamics to Survarium:

- like Artifact, it would have short "rounds" requiring 5 round "wins" for mission win, and _NO respawn tickets_
- like TDM, it would have _no other objective than killing_ whole enemy team; whichever team has more SURVIVING members at round end, wins the round
- in order to discourage rushing tactics, "short round" timeout would be increased eg. to 5-8mins and fewer rounds to fit inside 20m PvP mission time
- in order to encourage tactical movement, footsteps sound volume would be increased 100%
- gamemode would play on London (disabled sniper windows+scaffolding version), Vector (TDM version), Vostok (TDM version), School (TDM version), and Tarakanovsky fort (Slaughter version)