[Feature] Add support for reading a configuration file

[modeco80]

Title pretty much says it all.
My idea for this would be something like:

; Elfldr configuration file
elfldr {

	; The list of patches to enable.
	patches [
		memclr,
		hostfs
	]
	
	; specific configuration for patches and stuff
	hostfs_bigless true ; enable bigless mode

}

would mean I'd have to store a string->id mapping of patches, or scrap numerical patch IDs, but, meh.