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).

Also greatly refactors libstratosphere, and does a lot of other things.
There is a lot of code in this one.

* boot2: Simplify g_additional_launch_programs

It appears that Stratosphère is targeting C++17. In C++17,
std::make_tuple is not required for initialisating a tuple anymore.
Same thing, but less typing

* Replace std::make_tuple with {}

More readable and less noise. Also fixes two missing return statements.