We can just use the variant of std::string's replace() function that can
replace an occurrence with N copies of the same character, eliminating
the need to allocate a std::string containing a buffer of spaces.

Easy TODO

* More improvements to GDBStub
- Debugging of threads should work correctly with source and assembly level stepping and modifying registers and memory, meaning threads and callstacks are fully clickable in VS.
- List of modules is available to the client, with assumption that .nro and .nso are backed up by an .elf with symbols, while deconstructed ROMs keep N names.
- Initial support for floating point registers.

* Tidy up as requested in PR feedback

* Tidy up as requested in PR feedback

convert input buffer (std::vector<u8>) to string, stripping zero chars

Given we utilize fmt, we don't need to provide our own functions for formatting anymore

Add a new set of logging macros based on fmtlib
Similar but not exactly the same as https://github.com/citra-emu/citra/pull/3533

Citra currently uses a different version of fmt, which does not support FMT_VARIADIC so
make_args is used instead. On the other hand, yuzu uses fmt 4.1.0 which doesn't have make_args yet
so FMT_VARIADIC is used.

This makes clang-format useful on those.

Also add a bunch of forgotten transitive includes, which otherwise
prevented compilation.

The char16_t/char32_t implementations aren't present in the library and
cause linker errors. This is a known issue that wasn't fixed in VS2015
RTM.

Instead of forcibly taking the last 4 characters, it now finds the last extension separator (the period) and takes a substr of its location.