Update upstream B/CB/S

Adds /paper command for reloading the paper config.
Closes GH-639

Per-world config logging has been removed in favor of all or nothing
logging for all paper settings. I don't believe it was used enough to
warrant maintaining. If this is not the case it should be possible to
re-add it.

Spigot-Server-Patches/Fix-FallingBlocks-being-stuck-on-fences.patch

@@ -11,7 +11,7 @@ We now first check, if if we are already on the ground.
 if not, we check if the falling block is inside of the hitbox of the block at y - 1.
 
 diff --git a/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java b/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java
-index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
+index c4acb7597..7bd745a27 100644
 --- a/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java
 +++ b/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java
 @@ -0,0 +0,0 @@ public class PaperWorldConfig {
@@ -25,7 +25,7 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
 +    }
  }
 diff --git a/src/main/java/net/minecraft/server/BlockFalling.java b/src/main/java/net/minecraft/server/BlockFalling.java
-index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
+index dcdae998c..3c777418b 100644
 --- a/src/main/java/net/minecraft/server/BlockFalling.java
 +++ b/src/main/java/net/minecraft/server/BlockFalling.java
 @@ -0,0 +0,0 @@ public class BlockFalling extends Block {
@@ -42,7 +42,7 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
  
      public void b(World world, BlockPosition blockposition) {}
 diff --git a/src/main/java/net/minecraft/server/EntityFallingBlock.java b/src/main/java/net/minecraft/server/EntityFallingBlock.java
-index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
+index bb01929e8..8059e6dcd 100644
 --- a/src/main/java/net/minecraft/server/EntityFallingBlock.java
 +++ b/src/main/java/net/minecraft/server/EntityFallingBlock.java
 @@ -0,0 +0,0 @@ package net.minecraft.server;