Per-map parallax support (#9786)

* Per-map parallax support

* Comments for future sloth

* c

* bet

* Fix exception

* VV support

* Fix parallax

* mem

* weightless sounds

* Gravity stuff

* placeholder coz im too lazy to stash don't @ me son

* decent clouds

* sky

* Fast parallax

* Imagine spelling

* Loicense

* perish

* Fix weightless status

Co-authored-by: metalgearsloth <metalgearsloth@gmail.com>

Content.Client/Gravity/GravitySystem.cs

@@ -2,7 +2,7 @@ using Content.Shared.Gravity;
 
 namespace Content.Client.Gravity
 {
-    internal sealed class GravitySystem : SharedGravitySystem
+    public sealed class GravitySystem : SharedGravitySystem
     {
 
     }