Made the PulseManager capable of running multiple pulses simultaneously, in different slots (this makes it function a bit more like an entity queue, though not quite)

Fixed the dupe in the ectofuntus by demoting the action pulses for grinding bones from world pulses to individual pulses, and correcting a bit of the logic
Added function to remove multiple attributes at once to the ContentAPI

Server/src/main/kotlin/api/ContentAPI.kt

@@ -788,7 +788,11 @@ fun <T> setAttribute(entity: Entity, attribute: String, value: T) {
 }
 
 fun removeAttribute(entity: Entity, attribute: String) {
-    entity.removeAttribute(attribute)
+    entity.removeAttribute(attribute.replace("/save:",""))
+}
+
+fun removeAttributes(entity: Entity, vararg attributes: String) {
+    for (attribute in attributes) removeAttribute(entity, attribute)
 }
 
 /**