This converts the machine and mob processes to the SMC. Additionally, it
adds the Atom subsystem, which handles all Initialize() calls in place
of the old gameticker. Due to incompatibility with our atmospherics
(FUCK OUR ATMOSPHERICS FOR FUCKING EVER JESUS CHRIST WHO THE FUCK MADE
THIS PIECE OF GODDAMN SHIT) atmospherics machines do not use
Initialize() as they should, instead opting for a custom atmos_init
proc that the air controller handles.
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.
