humans swapping position via bumping with help intent now calls Crossed()

Signed-off-by: Cael_Aislinn <cael_aislinn@yahoo.com.au>
fixes an issue where wormholes would sometimes teleport to other zlevels, sped up teleporting by using range() instead of circlerangeturfs(), makes teleporting only pick turfs from the same zlevel as the target

Signed-off-by: Cael_Aislinn <cael_aislinn@yahoo.com.au>