Delay MOVEs/PUTs if the element label in question is part of the tree

Say we have two labels, A and B. Imagine this sequence: B is deleted, A is moved to B, and a new A is written. Our current compiler doesn't handle this.

This solution delays the execution of the MOVE and POST (new) action if there's already an element in the tree. It keeps trying each until it works or the number of delayed actions is no longer decreasing (to prevent an infinite loop).