Currently, to_chat is literally just a proc that does user << message.
But it'll let us do output modification in the future, especially for
something like Goon's HTML chat.
Big thanks to PJB for his to_chat script, see
https://github.com/d3athrow/vgstation13/pull/6625 for more details.
This commit first and foremost ports the -tg- atom pooling system, and
removes the old experimental system entirely.
Secondly, this PR modifies the qdel system to use a -tg- lookalike
"destroy hint" system, which means that individual objects can tell qdel
what to do with them beyond taking care of things they need to delete.
This ties into the atom pooling system via a new hint define,
QDEL_HINT_PUTINPOOL, which will place the atom in the pool instead of
deleting it as per standard.
Emitter beams are now fully pooled.
Qdel now has semi-compatibility with all datum types, however it is not
the same as -tg-'s "Queue everything!" system. It simply passes it through
the GC immediately and adds it to the "hard del" lists. This means that
reagents can be qdel'ed, but there is no purpose as of yet, as it is more
or less the same as just deleting them, with the added effect of adding
logs of them being deleted to the garbage collector.
