## About The Pull Request
It isn't really an issue now, but these will be used more in future, so
let's start off strong.
There's a lot of work going on here that doesn't really need to be
happening, mostly off not knowing a trickTM.
Biggest one is vis_locs and vis_contents are linked lists, being in one
requires being in another. Atoms clear out their vis_locs on Destroy, so
we do not need to "own" references to things that have us in their
vis_contents.
This combined with knowing our old loc's loc off Moved made the use of
weakrefs here unneeded. Similarly, atoms inside atom movables qdel on
when the upper layer is deleted, so most cases of the qdeleting signal
were unneeded.
Also, we only cared about movement if we were an item (speaking of
which, I swapped out the isitem stuff with a flag that gets passed into
the new() call)
## Why It's Good For The Game
Speed
Loosely adapted from /vg/. This is an entity component system for adding behaviours to datums when inheritance doesn't quite cut it. By using signals and events instead of direct inheritance, you can inject behaviours without hacky overloads. It requires a different method of thinking, but is not hard to use correctly. If a behaviour can have application across more than one thing. Make it generic, make it a component. Atom/mob/obj event? Give it a signal, and forward it's arguments with a SendSignal() call. Now every component that want's to can also know about this happening.
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