Water flow logic tweaking:

- Less fluctuation, water doesn't constantly flow back and forth through gaps.
- Flowing water pushes characters around much more heavily, and the force is applied to the collider in addition to the limbs.
- Vertical gaps don't push characters up/down unless the character is roughly above/below the gap.

+ Renamed some fields in the hull and gap classes (Volume -> WaterVolume, FullVolume -> Volume, public fields start with a capital letter)

Barotrauma/BarotraumaShared/Source/Networking/RespawnManager.cs

@@ -365,7 +365,7 @@ namespace Barotrauma.Networking
                 if (hull.Submarine != respawnShuttle) continue;
 
                 hull.OxygenPercentage = 100.0f;
-                hull.Volume = 0.0f;
+                hull.WaterVolume = 0.0f;
             }
 
             foreach (Character c in Character.CharacterList)