Update Paper to MC 1.12

Spigot-Server-Patches/Toggleable-Elytra-Wall-Damage.patch

@@ -21,13 +21,13 @@ index ef60c15bd..cec9ea74c 100644
 +    }
  }
 diff --git a/src/main/java/net/minecraft/server/EntityLiving.java b/src/main/java/net/minecraft/server/EntityLiving.java
-index 9587704d7..97b498507 100644
+index 3d1897d6f..e50f7a3ca 100644
 --- a/src/main/java/net/minecraft/server/EntityLiving.java
 +++ b/src/main/java/net/minecraft/server/EntityLiving.java
 @@ -0,0 +0,0 @@ public abstract class EntityLiving extends Entity {
                      this.motY = 0.30000001192092896D;
                  }
-             } else if (this.cN()) {
+             } else if (this.cP()) {
 +                if (world.paperConfig.elytraHitWallDamage) { // Paper start - Toggleable Elytra Wall Damage
                  if (this.motY > -0.5D) {
                      this.fallDistance = 1.0F;