Removed NanoVG and added latest ImGui code
Latest Git version of ImGui
Latest bx and bgfx
Updated to latest ImGui
Readded nativeContext() & d3d12.cpp to build cfg.
Removed no-needed file
Added compiling of BGFX_SHADERC
Added more support for Shaderc

Also added some test shaders taken from 01-Cubes example
Added File_loadToMemory and unit_test for it
Working temporary rendering
Removed some comments
WIP on rendering
Correct display of ImGui frame
Working rendering of ImGui
Removed double setup
Added generated files
Hacky removal of DX9 support
Implemented nativeContext for DX11
Fixes so bgfx_shaderc builds on Windows
Fixed so usage of alloca.h works