This commit refactors the area ambient sound system to pick from a list
defined on the area definition itself instead of a lengthy else-if change.
This is mostly noticable to people making new areas or modifying area
ambient sounds.
This commit also adds 5 maintnance ambient sounds from -tg-.
A port of https://github.com/d3athrow/vgstation13/pull/4377

Allows brooms to be wielded with 2-hands. Doing so places the broom
between your legs so you look like you are riding it.
You can also put a horsehead mask onto the broom to create a stick-horse
to ride. This can also be wielded, but will ALWAYS appear between your
legs.
And for the more magically inclined, wielding a broom or stick-horse (2
hands!) will cause you to ride it like a witch, giving you the ability
to bypass hazards such as tables and banana peels.
This commit overhauls the global.dm file, global_lists.dm file, and
defines.dm file into a tree system based on -tg-.
All defines have been split and distributed in code/__DEFINES/
Everything from global.dm and global_lists.dm has been split and
distributed in code/_globalvars
The _compile_options.dm file contains anything that absolutely, 100%, must
be initialized before world.dm.
Name definitions have been moved to code/_globalvars/lists/names.dm.
Other things to note
- All instances of something.z == 2/1/3/5 have been replaced with easily
configurable defines, labeled ZLEVEL_. The map include file can
override these by defining custom ones in it's file, as it is at the
top of the tree.
- Also adds ABSTRACT and NODROP flags in preparation for removal of
canremove and abstract vars.
- Sorts some of the setup.dm flags so they're in order.
- Replaces 'flags & 2' in policetape.dm with pass_flags & PASSTABLE,
should have the same effect.
- Adds the ability to construct Syndicate Medbots, which were previously
in the code but unable to be constructed. These bots will only heal
Syndicate Nukeops, and can only be made from the medikit box that
Nukeops can purchase.
- Fixed recharging in energy crossbows and laser tag guns, they were
recharging 10x slower than they were meant to.
exactly as the title says, though, the smelter menu calls it 'clown',
because the oretag is clown, didn't fix it, because i dont know what
things use the oretag variable(i know some), and didn't want to break
anything over such a small bug
Ores only count towards the station's score if it spawns on Z=5 (Mining
Asteroid Level). The old method caused errors in the server log because
gameticker/ticker initialized after the map ore spawns.
This also means that ore mined on the Clown Planet don't count.