All service calls in the CTR OS return result codes indicating the
success or failure of the call. Previous to this commit, Citra's HLE
emulation of services and the kernel universally either ignored errors
or returned dummy -1 error codes.

This commit makes an initial effort to provide an infrastructure for
error reporting and propagation which can be use going forward to make
HLE calls accurately return errors as the original system. A few parts
of the code have been updated to use the new system where applicable.

One part of this effort is the definition of the `ResultCode` type,
which provides facilities for constructing and parsing error codes in
the structured format used by the CTR.

The `ResultVal` type builds on `ResultCode` by providing a container for
values returned by function that can report errors. It enforces that
correct error checking will be done on function returns by preventing
the use of the return value if the function returned an error code.

Currently this change is mostly internal since errors are still
suppressed on the ARM<->HLE border, as a temporary compatibility hack.
As functionality is implemented and tested this hack can be eventually
removed.

These functions are not referred to by their linkage name outside of the translation unit, so they can be marked as static.

Changed HLE function return methods to be static inline functions.

Most functions already operate on std::strings. This also removes the need to manually null terminate thread names.

entry_point would not be added to the string. Also used StringFromFormat
so that the buffer is unnecessary.

AddressArbiter: Added documentation comment, fixed whitespace issue.

AddressArbiter: Fixed incorrect comment, reordered if-statement to be more clear.

SVC: Removed trailing whitespace.

- Also added some safety checks to MapSharedMemory.

- Previously, used a hard-coded shared memory handle of 0x10002000 (as used by libctru homebrew)

GSP: Added name for shared memory.

GSP: Cleaned up assertion message.

- SVC: Added ExitThread support
- SVC: Added SignalEvent support
- Thread: Added WAITTYPE_EVENT for waiting threads for event signals
- Thread: Added support for blocking on other threads to finish (e.g. Thread::Join)
- Thread: Added debug function for printing current threads ready for execution
- Thread: Removed hack/broken thread ready state code from Kernel::Reschedule
- Mutex: Moved WaitCurrentThread from SVC to Mutex::WaitSynchronization
- Event: Added support for blocking threads on event signalling

Kernel: Added missing algorithm #include for use of std::find on non-Windows platforms.

kernel: changed main thread priority to default, updated Kernel::Reschedule to use PrepareReschedule

svc: updated waitSychronization to not overwrite handle on return, added stub for SleepThread (does nothing)

- force kernel reschedule after svcWaitSynchronization
- fixed some bugs with passing in pointer arguments
- cleaned up some comments and log messages

svc: changed SendSyncRequest to use Kernel::Object SyncRequest (instead of just service Interface class)

svc: added a check to ensure that a service was implemented before attempting to connect to its port

thread: removed unused SwitchContext/Reschedule reason field, added missing arg parameter to SVC CreateThread

svc: added Kernel::Reschedule to svc WaitSynchronization1, updated log messages to include newly created handles