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

Bukkit Changes:
ccb9614e #548: LivingEntity - add methods for getting/setting invisibility

CraftBukkit Changes:
f8d4da08 #743: LivingEntity - add methods for getting/setting invisibility

Spigot Changes:
17d78dbd Rebuild patches

Spigot-API-Patches/Add-methods-for-working-with-arrows-stuck-in-living-.patch

@@ -9,9 +9,9 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
 --- a/src/main/java/org/bukkit/entity/LivingEntity.java
 +++ b/src/main/java/org/bukkit/entity/LivingEntity.java
 @@ -0,0 +0,0 @@ public interface LivingEntity extends Attributable, Damageable, ProjectileSource
+      * @return Whether the entity is invisible
       */
-     @NotNull
-     public EntityCategory getCategory();
+     public boolean isInvisible();
 +
 +    // Paper start
 +    /**