support 16-bit X86

[tomsons26]

By doing these hacks in src/arch/x86.rs it's possible to load a 16 bit coff and it correctly disassembles
in
Decoder::with_ip(
change Architecture::X86 => 32, to Architecture::X86 => 16,

in
Architecture::X86 => match flags {
add

                RelocationFlags::Coff(pe::IMAGE_REL_I386_DIR16 | pe::IMAGE_REL_I386_REL16) => {
                    let data = 
                        section.data()?[address as usize..address as usize + 2].try_into()?;
                    Ok(self.endianness.read_i16_bytes(data) as i64)
                }

Proper 16 bit support would be much better of course
A setback seems that object module assumes X86 is 32 bit and doesn't reserve a 16-bit Architecture