This fixes a build issue on gcc 6 due to -Werror and a warning caused
by boost::optional, see:
https://github.com/MerryMage/dynarmic/issues/83

Qt cleanup

Fixes #2556

Added drag and drop feature to the code

core: add missing errors.h in CMakeLists.txt

Qt/GameList: Use suffix() to parse the file extension

Fixes #2567

added http service enum to the log.h file

completeSuffix returns everything after the first period, which means
that a file such as `foo.bar.3ds` would not get recognized.

Re-organize software rasterizer code

file_sys: change RomFS archive to Self NCCH archive

Small VideoCore cleanups

Fixes #2455

The resulting pointer wasn't written to unless the index was verified as
valid, but that's still UB and triggered debug checks in MSVC.

Reported by garrettboast on IRC

This eliminates UB when aliasing it with the array of u32 regs, and
is compatible with non-LE architectures.