* Wrap >4-char literals in a MULTI_CHAR macro

Modern compilers do not support CW's non-standard behavior with
>4 char literals. We can, however, use a constexpr function to
compute the u64 values directly. This leaves <=4 char literals
unchanged.

* Replace non-pointer usages of NULL with 0

* Define NULL to nullptr on C++11 and above

* Fix more -Wpointer-arith and -Woverflow warnings

* Replace u32/s32 with uintptr_t/intptr_t where appropriate

* JSUOutputStream: Overload all standard int types

* Fix 6-byte multichar literals

* Add `struct` to `e_ga_class::ga_s`

* Fix remaining wrong forward declares (struct/class)

* Replace `#include <string>` with `#include <cstring>`

* Guard FLT_EPSILON define to prevent redefinition

* Add missing `#include <cstring>` for direct cstring function usage

* move math to cmath

* replace stdarg to cstdarg

* change stdint to stdint.h

* minor fixes

* change stdio to cstdio

* change stdlib to stdlib

* renamed ctype to cctype

* fix missing argument for UNSET_FLAG

* Last fix for standard compiler error

* adding define guards around headers

* rename cmath.h and climits.h to cmath and climits respectively

* renaming cstdarg.h to cstdarg

* renaming cstdlib.h to cstdlib

* renaming cstring.h to cstring

* renaming cstdio.h to cstdio

* renaming cmath locale ctype

* renaming stdarg string and va_list

* renaming cstddef

* renaming stdio stddef stdlib

* renaming algorithm, functional, iterator, memory, and utility

* renaming bitset, cstdint, limits, and stdint

* renaming new and type_traits

* update quote includes for standard library headers to angle bracket includes

* msl_c header cleanup

* math header cleanup

* fix rest of shieldD configs

* cleanup cflag configs a bit

* fix shield build

* Adding explicit dolphin/ prefix & fix characters

* Rename ShiftJIS to SJIS

* Separate JASSeqReader read methods implementation between compilers.

* Fix pointer.h

* fix d_item_data typo

* fix gcn matching issue

* some wii OS fixes

* remove old dol2asm comments

* remove dol2asm.h

* remove function address comments

* normalize ATTRIBUTE_ALIGN usage

* DECL_WEAK macro

* fix gcc attribute weak macro

* wrap more mwcc specific things in ifdefs

* fixes

* fix revo sdk version flags

* fixes