* fs.mitm: skeleton the use of special allocation in romfs build

* pm: add api for ams.mitm to steal application memory

* pm/mitm: okay, that api won't work, try a different one

* romfs: revert memory usage increases; we'll handle torture games case-by-case.

* pm/romfs: first (broken?) pass at dynamic heap.

I cannot wait to figure out all the ways this is wrong.

* Release the dynamic heap a little more eagerly

* romfs: animal crossing is also not a nice game

* romfs: fix issues in close-during-build

* romfs: zelda is a blight upon this earth

WebApplet crashes on exit with 16 more MB stolen, apparently.

* result: try out some experimental shenanigans

* result: sketch out some more shenanigans

* result: see what it looks like to convert kernel to use result conds instead of guards

* make rest of kernel use experimental new macro-ing

* ams: update to build with gcc10/c++20

* remove mno-outline-atomics

* ams: take care of most TODO C++20s

* fusee/sept: update for gcc10

* whoosh, your code now uses pre-compiled headers

* make: dependency fixes

Previously, we were only setting resource limit,
which didn't modify actual reserved pool size for
the system pool. This adds kernel patches which reduce
the applet pool size, granting the extra memory to
the system partition. The given value has been chosen
specifically to allow normal applet usages. Further
reduction may result in crashes during normal applet usage.

namespace sts::ams -> ams::exosphere, ams::.

This is to facilitate future use of ams:: namespace code in
mesosphere, as we'll want to include ams::util, ams::result, ams::svc...

Because I was working on multiple things at once, this commit also:
- Adds wrappers for/linker flags to wrap CXX exceptions to make them
  abort. This saves ~0x8000 of memory in every system module.
- Broadly replaces lines of the pattern if (cond) { return ResultX; }
  with R_UNLESS(!cond, ResultX());.
- Reworks the R_TRY_CATCH macros (and the result macros in general).