mob dead state tweaks (#162)

~~well, it SHOULD make mob rotate on death, but it doesn't, i have no idea why~~

- Blocks character movement in crit/death
- rotates character ~~360noscope~~ 90 degrees to convince you it's lying down when dead

resolves #145
resolves #158
related to #115

Content.Client/GameObjects/Components/Mobs/SpeciesVisualizer2D.cs

@@ -0,0 +1,35 @@
+using Content.Shared.GameObjects.Components.Mobs;
+using SS14.Client.GameObjects;
+using SS14.Client.Interfaces.GameObjects.Components;
+using SS14.Shared.Interfaces.GameObjects;
+using SS14.Shared.Maths;
+
+namespace Content.Client.GameObjects.Components.Mobs
+{
+    public class SpeciesVisualizer2D : AppearanceVisualizer
+    {
+        public override void InitializeEntity(IEntity entity)
+        {
+            base.InitializeEntity(entity);
+        }
+
+        public override void OnChangeData(AppearanceComponent component)
+        {
+            base.OnChangeData(component);
+
+            var sprite = component.Owner.GetComponent<ISpriteComponent>();
+            if (component.TryGetData<SharedSpeciesComponent.MobState>(SharedSpeciesComponent.MobVisuals.RotationState, out var state))
+            {
+                switch (state) 
+                {
+                    case SharedSpeciesComponent.MobState.Stand:
+                        sprite.Rotation = 0;
+                        break;
+                    case SharedSpeciesComponent.MobState.Down:
+                        sprite.Rotation = Angle.FromDegrees(90);
+                        break;
+                }
+            }
+        }
+    }
+}