Move GLES20 source into standard locations
Move Khronos headers into their respective components, to be exported by each.
Remove hostthreadadapter as nothing outside of the vghwapiwrapper, which now contains the code, needs it
#ifndef _WINRESRC_H
#define _WINRESRC_H
#if __GNUC__ >=3
#pragma GCC system_header
#endif
#define WIN32_LEAN_AND_MEAN
#include <winuser.h>
#include <winnt.h>
#include <winver.h>
#include <dde.h>
#include <dlgs.h>
#include <commctrl.h>
#endif