Replaces `std::shared_pointer` with `stx::atomic_ptr` and `stx::shared_ptr`.
Notes to programmers:
* This pr kills the use of `dynamic_cast`, `std::dynamic_pointer_cast` and `std::weak_ptr` on IDM objects, possible replacement is to save the object ID on the base object, then use idm::check/get_unlocked to the destination type via the saved ID which may be null. Null pointer check is how you can tell type mismatch (as dynamic cast) or object destruction (as weak_ptr locking).
* Double-inheritance on IDM objects should be used with care, `stx::shared_ptr` does not support constant-evaluated pointer offsetting to parent/child type.
* `idm::check/get_unlocked` can now be used anywhere.
Misc fixes:
* Fixes some segfaults with RPCN with interaction with IDM.
* Fix deadlocks in access violation handler due locking recursion.
* Fixes race condition in process exit-spawn on memory containers read.
* Fix bug that theoretically can prevent RPCS3 from booting - fix `id_manager::typeinfo` comparison to compare members instead of `memcmp` which can fail spuriously on padding bytes.
* Ensure all IDM inherited types of base, either has `id_base` or `id_type` defined locally, this allows to make getters such as `idm::get_unlocked<lv2_socket, lv2_socket_raw>()` which were broken before. (requires save-states invalidation)
* Removes broken operator[] overload of `stx::shared_ptr` and `stx::single_ptr` for non-array types.
-Indentation warnings
-prevent shift overflow
-This was declared extern in all contexts. Remove this for initialization
-Fix main return types. OH CANADA!
-Silence extraneos 'unused expression' warning
-Force use return value (warning)
-Remove tautological compare copy-pasta (char always < 256)
Also renames "AudioThread" to "AudioBackend". The new name is more
descriptive of what the class really is responsible for, since the
backends are not responsible for managing the audio thread.
NOTE: Right now only XAudio2 is supported
* Optimizations
1) Some headers simplified for better compilation time
2) Some templates simplified for smaller executable size
3) Eliminate std::future to fix compilation for mingw64
4) PKG installation can be cancelled now
5) cellGame fixes
6) XAudio2 fix for mingw64
7) PPUInterpreter bug fixed (Clang)
* any_pod<> implemented
Aliases: any16, any32, any64
rsx::make_command fixed
