New chat events for better Adventure support (#5289)

Bump Adventure to 4.6.0

fixes #5216
fixes #5261
fixes #5287

Spigot-API-Patches/0209-Expose-Arrow-getItemStack.patch

@@ -0,0 +1,25 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Nesaak <52047222+Nesaak@users.noreply.github.com>
+Date: Fri, 22 May 2020 13:35:21 -0400
+Subject: [PATCH] Expose Arrow getItemStack
+
+
+diff --git a/src/main/java/org/bukkit/entity/AbstractArrow.java b/src/main/java/org/bukkit/entity/AbstractArrow.java
+index e8e56e89e32d84af0639fe2e9b0eeabd747b6007..b1d8007eed489aa061c1a6813bcdafc101231e56 100644
+--- a/src/main/java/org/bukkit/entity/AbstractArrow.java
++++ b/src/main/java/org/bukkit/entity/AbstractArrow.java
+@@ -143,6 +143,14 @@ public interface AbstractArrow extends Projectile {
+     }
+ 
+     // Paper start
++    /**
++     * Gets the ItemStack for this arrow.
++     *
++     * @return The ItemStack, as if a player picked up the arrow
++     */
++    @NotNull
++    org.bukkit.inventory.ItemStack getItemStack();
++
+     /**
+      * Gets the {@link PickupRule} for this arrow.
+      *