Add sigils for assembly?

[jbush001]

Nyuzi assembly uses a minimal assembly form with no sigils (character prefixes that indicate type). However, when there are typos, this can result in confusing error messages and may let bugs slip through. It might be useful to add more specific type specifiers.

Quick survey of other architectures:

	Register	Relocation	Immediate Value
Mips	$3	%got(var)	24
PowerPC	%r12	var@got	25
x86 (gas)	%eax	var@got	24
AArch64	x3	:gottprel:var	#7
ARM	r7	n/a	#7
Nyuzi	s8/v9	got(foo)	12