Updated Upstream (Bukkit/CraftBukkit/Spigot)

Upstream has released updates that appears to apply and compile correctly.
This update has not been tested by PaperMC and as with ANY update, please do your own testing

Please note that this build includes changes to meet upstreams
requirements for nullability annotations. While we aim for a level of
accuracy, these might not be 100% correct, if there are any issues,
please speak to us on discord, or open an issue on the tracker to
discuss.

Bukkit Changes:
9a6a1de3 Remove nullability annotations from enum constructors
3f0591ea SPIGOT-2540: Add nullability annotations to entire Bukkit API

CraftBukkit Changes:
8d8475fc SPIGOT-4666: Force parameter in HumanEntity#sleep
8b1588e2 Fix ExplosionPrimeEvent#setFire not working with EnderCrystals
39a287b7 Don't ignore newlines in PlayerListHeader/Footer

Spigot Changes:
cf694d87 Add nullability annotations

Spigot-API-Patches/0010-Add-player-view-distance-API.patch

@@ -1,14 +1,14 @@
-From e802df27e5944819165eb81c78b5c6e4842a15dd Mon Sep 17 00:00:00 2001
+From 331efa882680033d3d69d00d3717886572cf5051 Mon Sep 17 00:00:00 2001
 From: Byteflux <byte@byteflux.net>
 Date: Mon, 29 Feb 2016 18:05:37 -0600
 Subject: [PATCH] Add player view distance API
 
 
 diff --git a/src/main/java/org/bukkit/entity/Player.java b/src/main/java/org/bukkit/entity/Player.java
-index 694254f1..d72a7e3d 100644
+index 95ebf016..51a145a4 100644
 --- a/src/main/java/org/bukkit/entity/Player.java
 +++ b/src/main/java/org/bukkit/entity/Player.java
-@@ -1468,6 +1468,20 @@ public interface Player extends HumanEntity, Conversable, OfflinePlayer, PluginM
+@@ -1480,6 +1480,20 @@ public interface Player extends HumanEntity, Conversable, OfflinePlayer, PluginM
       */
      public void updateCommands();
  
@@ -30,5 +30,5 @@ index 694254f1..d72a7e3d 100644
      public class Spigot extends Entity.Spigot
      {
 -- 
-2.20.1
+2.21.0