This splits all of the sections into completely self-contained parts.

This section was bound together by a single reference from
TiffanyFamilyMembers to the end of the bank. Probably caused by the
translators.

It isn't related to the player object at all.

Want to ask people what the best course of action for these would be.

This will make the `.o` file splitting easier later down the line.

Some more splitting is required to finish making main.asm INCLUDE-only, however.

Moved the core part of anim_commands out to core, and included the
entire battle anim engine there.

This is a rather small and inconsequential part of the (spaghetti)
codebase, and I want to move on to the rest of this mess.

These can't really be split. The only reason they're being made separate
sections is to maintain consistency with the rest of the map scripts.

This will help people move them around, if need be.
This should be removed as soon as rgbds supports this.

Things like split some "generic" files into multiple specific files, or
some big files into multiple, or join some sections.
Thing is, splitting the sections like this gives us great insight into
what goes where, and what is or isn't related.
This commit doesn't yet throw away strict ROM order, however.

ChrisBackpic is split away as well, and it makes sense they're somewhere
together.

Data is always secondary, unless independent somehow.

This commit is the start of what I call "the `.o` split".
Sadly, this split has made the entire build system _magnitudes_ slower.
As such, I will try to make it less slow, and hopefully improve the
incremental build times, and later the build time overall.

But, if it doesn't work out, this can always be reverted.

Exported all necessary cross-file labels, and unexported the unnecessary
exports. This makes the linker much, much faster.

This makes incremental builds really, really fast!

This will make sure only necessary symbols are ever exported, except for
everything in the ram sections, of course, which doesn't make sense to
not be exported.

engine/predef.asm and engine/events/specials.asm are ignored because the
arrays generate a bunch of symbols that are unused, but we can't really
not export some of them since we use a macro.

I'm not entirely sure where I'm going with this yet.

This noticeably increases rebuild times by 10 seconds and causes every
single map to be rebuilt when certain constants change, even if they're
unnecessary, but such is life.

This new makefile introduces the following features:
- A build/ directory
- A version/ directory where all the differences between each version
will be kept
And this while hopefully keeping all features we used to have.

As suggested by @Rangi42:
- Add `tidy` target
- Additional comment for the `else` case in the main Makefile
- Add `version/crystal.mk` for consistency
- Use `.mkdir` as file-creation marker

- Moved main.asm to gfx/misc.asm
- Created constant for the two pics sections
- Moved the stadium bins into version/
- Move some graphics rules into gfx/gfx.mk

With the new Makefile, some changes are required...

I wonder when we'll just start forcing Mac users to switch to a more
recent version of GNU Make. This version is only 5 years younger than
the ROM we're reversing...

https://i.imgflip.com/so5ya.jpg

floating_constants.inc was moved out of maps_common.inc because it's not
something that is necessary for new maps - it's supposed to be the
exception, not the norm.

Since there's only four maps that use BattleTowerAction, and the
battle_tower_constants.inc aren't otherwise used anywhere, they're now
only included where required.

TODO comments are the worst thing invented by mankind, yet I love using
them for some reason...

…itting

An RGBDS update has made it possible to remove these, by adding proper
multicharmap support.

Add documentation for the usage of the new makefile, as I'm sure it'll
confuse some people.

…itting

…itting

- Copy the files when running `make` without arguments
- Clean topdir files when running `make tidy`
- Remove `-march=native` as this doesn't work with `clang`

They're arbitrary names, and the .asm part is redundant

🕯️

Apparently there's a very sneaky non-banked reference between these,
that will cause the game to crash if these are not in the same bank.

Unneccessarily "generic" file, also didn't make sense now pokedex_2 is
gone.

These strings are right at the end of generic_callee, but for
convenience I'll move them out to a separate file, for now at least.