VerletTime is failing

[mariajinxue]

@removeAgent is failing when I evolve the 'seeker_killer' ABM in the notebook attach: https://drive.google.com/file/d/12HwsVhFKVlP934NwTsDEbUWcssVnIVlZ/view?usp=drive_link

[gatocor]

After checking it looks that VerletList sometimes takes the same cell as a neighbor.
A possible cause is that after removing a cell and reassigning positions in the array, it does not recompute the list again and may be the case that the cell contains itself in the list, looping over itself as if it was a neighbor.
I will look into that.