just to change from disabling spawn chunks to control over its size. Removes disableSpawnChunks, adds spawnChunksSize. Fixes #192

src/main/java/carpet/mixins/ServerWorld_spawnChunksMixin.java

@@ -0,0 +1,17 @@
+package carpet.mixins;
+
+import carpet.CarpetSettings;
+import net.minecraft.server.world.ServerWorld;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.Constant;
+import org.spongepowered.asm.mixin.injection.ModifyConstant;
+
+@Mixin(ServerWorld.class)
+public class ServerWorld_spawnChunksMixin
+{
+    @ModifyConstant(method = "setSpawnPos", constant = @Constant(intValue = 11), expect = 2)
+    private int pushLimit(int original)
+    {
+        return CarpetSettings.spawnChunksSize;
+    }
+}