* Changed LobbyMusiccollection over to a Cvar and edited ContentAudioSystem.cs to use Cvar Values
* Addedd Ability to modify the lobbyMusiccollection from the command line
* Fixed changing lobby music while in the round
* Deleted uneeded duplicate line
* Removed additional duplicate lobbyplaylist line
* Alphabatized imports and refactored to use Subs.CVar
* Added error checking and default behaviour to CVar sub.
* Refactored to use TryIndex and Allowed for a empty soundcollection when a sound collection is not found. Edited Cvar comment to reflect changes.
* Made _lobbyMusicCollection nullable and addedd handling for null case where used. Also Changed LobbyMusicCollection Cvar over to audio rather than ambience.
* Update Content.Server/Audio/ContentAudioSystem.cs
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Co-authored-by: Pieter-Jan Briers <pieterjan.briers@gmail.com>
* fix: lobby music volume will be changed on options change without restart (also lobby music not looped anymore)
* refactor: now lobby music is part of ContentAudioSystem. Lobby playlist is used instead of single track. Client now selects next lobby soundtrack after previous finished.
* refactor: incapsulated info on current lobby track in simple record
* refactor: fixed inconsistent naming between song and soundtrack for lobbymusic
* refactor: xml-doc for LobbyPlaylistChangedEvent
* fix: inverted invalid _audio.PlayGlobal check to return only if lobby soundtrack play call failed
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Co-authored-by: pa.pecherskij <pa.pecherskij@interfax.ru>
