Numerous fixes to entity related changes

While it wasn't really "broken" before, if plugins use NMS
(which they really should't be) and mess with entity management
themselves, and get it wrong, they could ultimately corrupt our
state expectations.

I've been unable to reproduce any issues locally, but these changes
are the result of me analyzing the code pretty deeply and seeing
about how to make it more durable to abnormal usage.

Any servers seeing oddities, please run with -Ddebug.entities=true
and send me any logs triggered.

Spigot-Server-Patches/Add-exception-reporting-event.patch

@@ -49,7 +49,7 @@ index 0000000000..f699ce18ca
 +    }
 +}
 diff --git a/src/main/java/net/minecraft/server/Chunk.java b/src/main/java/net/minecraft/server/Chunk.java
-index d1b6344ced..446e464b72 100644
+index cb56d067b9..67cd4af4f5 100644
 --- a/src/main/java/net/minecraft/server/Chunk.java
 +++ b/src/main/java/net/minecraft/server/Chunk.java
 @@ -0,0 +0,0 @@
@@ -240,7 +240,7 @@ index 58122b18eb..0ac1fb53a4 100644
              }
  
 diff --git a/src/main/java/net/minecraft/server/World.java b/src/main/java/net/minecraft/server/World.java
-index 7e1df0e5b6..0684d85beb 100644
+index 09cf98ccdd..6e7c0c9da4 100644
 --- a/src/main/java/net/minecraft/server/World.java
 +++ b/src/main/java/net/minecraft/server/World.java
 @@ -0,0 +0,0 @@