Fix teleport bugging

Teleporting forcibly rounds locations because @fullwall edited the roundLocation function to return the original, now modified location, rather than clone it as is necessary to avoid trouble. This restores the original roundLocation which will avoid that error.
Improve NPC pseudo-respawning

In initial testing, longer periods were better. However, that was before
a lot of recoding... shorter periods are now superior and keeping
significantly more NPCs visible (When dealing with batches so large that
the system fails to load them all)
Merge pull request #147 from mcmonkey4eva/master

Fix teleport bugging