Roundstart Audio Replacement & Roundend Audio DLC #1 (#2837)

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## About The Pull Request
**SOUL REMOVAL**

Replaces the stock /tg/ welcome message with something a little more
relevant, and replaces all of our roundend audio clips with a few
shiptesting cultural touchstones.
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## Why It's Good For The Game
Out of all of the things we've inherited from /tg/station, the
roundstart/end audio clips were always fairly low on the list of things
that needed replacing. After hearing _Welcome to the station crew, enjoy
your stay_ and _Now departing /tg/station_ several hundred times over,
however, I finally think the soul has overstayed its welcome.

This helps us distinguish ourselves from other /tg/ downstreams in a
subtle but impactful way, hopefully giving new players a "We're not in
Kansas anymore" feeling and allowing veterans to point their finger at
the screen and go "I understood that reference!"
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## Changelog

:cl:
soundadd: several new roundend audio clips, as well as a new roundstart
clip
sounddel: all of the old roundend audio clips, as well as the old
roundstart clip
del: soul
/:cl:

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code/controllers/subsystem/ticker.dm

@@ -282,7 +282,7 @@ SUBSYSTEM_DEF(ticker)
 
 	to_chat(world, "<span class='notice'><B>Welcome to [station_name()], enjoy your stay!</B></span>")
 	SSredbot.send_discord_message("ooc", "**A new round has begun.**")
-	SEND_SOUND(world, sound('sound/ai/welcome.ogg'))
+	SEND_SOUND(world, sound('sound/roundstart/addiguana.ogg'))
 
 	current_state = GAME_STATE_PLAYING
 	Master.SetRunLevel(RUNLEVEL_GAME)
@@ -571,15 +571,12 @@ SUBSYSTEM_DEF(ticker)
 	update_everything_flag_in_db()
 	if(!round_end_sound)
 		round_end_sound = pick(\
-		'sound/roundend/newroundsexy.ogg',
-		'sound/roundend/apcdestroyed.ogg',
-		'sound/roundend/bangindonk.ogg',
-		'sound/roundend/leavingtg.ogg',
-		'sound/roundend/its_only_game.ogg',
-		'sound/roundend/yeehaw.ogg',
-		'sound/roundend/disappointed.ogg',
-		'sound/roundend/scrunglartiy.ogg',
-		'sound/roundend/petersondisappointed.ogg'\
+		'sound/roundend/deliguana.ogg',
+		'sound/roundend/undecided.ogg',
+		'sound/roundend/repair.ogg',
+		'sound/roundend/boowomp.ogg',
+		'sound/roundend/shiptestingthursday.ogg',
+		'sound/roundend/gayrights.ogg'\
 		)
 	///The reference to the end of round sound that we have chosen.
 	var/sound/end_of_round_sound_ref = sound(round_end_sound)