Simple boot code for x86 based systems

This is a single sector boot code that can be compiled to run in 16-bit real mode, 16-bit and 32-bit protected mode and 64-bit long mode.

To compile all 4 versions:

make

To run all 4 versions:

./run 16 ./run pm ./run 32 ./run 64

Requirements:

• Netwide Assembler
• Make
• Bare metal GCC compilers for ia16, i686 and x86_64
• QEMU system emulator for i386 and x86_64