Kenge kinks

- Loading ELF files
	- Must be able to load 64- and 32-bit elf files
	- Must link at the correct address:
	- When linking for Linux, the start address of the text is 
	specified minus the size of the elf header.
	- Because Kenge maps the ELF directly, this start address is 
	incorrect - we start executing the ELF header.
	- So we supply a custom linker script that specifies an offset for the
	start of text.
	- But if we supply a custom linker script we must also specify other
	things that would usually be provided by the linker's default
	link script. Importantly we must specify the start symbol (_start),
	which is defined in the crt. Otherwise the linker just uses the start
	of text. (-e _start in ldflags)