This was needed to make stratosphere buildable with debugging on.

os:: assertions rely on GetCurrentThread() working, and this requires
the global os resource manager to be constructed. However, __appInit executes
before global constructors. We now require that hos::InitializeForStratosphere()
be called before anything else is done. This initializes the os resource manager,
sets the hos version for libnx, and may do more things in the future.

TODO: Consider replacing __appInit/__appExit with ams:: namespace functions in general,
and wrap them so that we guarantee hos::InitializeForStratosphere is called first, and
generally ensure a consistent stratosphere environment.

This was tested using `https://github.com/node-dot-cpp/alloc-test` plus a few other by-hand tests.

It seems to work for the case we care about (sysmodules without thread cache-ing).

External users are advised to build with assertions on and contact SciresM if you find issues.

This is a lot of code to have gotten right in one go, and it was written mostly after midnight while sick, so there are probably un-noticed issues.

subrepo:
  subdir:   "libraries"
  merged:   "07af583b"
upstream:
  origin:   "https://github.com/Atmosphere-NX/Atmosphere-libs"
  branch:   "master"
  commit:   "07af583b"
git-subrepo:
  version:  "0.4.0"
  origin:   "https://github.com/ingydotnet/git-subrepo"
  commit:   "5d6aba9"