Preset variables

Charcoal has a few variables set to a certain value by default.

Variable	Verbose	Value
θ	q	First input.
η	h	Second input.
ζ	z	Third input.
ε	e	Fourth input.
δ	d	Fifth input.
γ	g	ASCII printables.
β	b	Lowercase letters from a to z.
α	a	Uppercase letters from A to Z.
ω	w	The empty string.
ψ	y	Null byte.
χ	c	10.
φ	f	1000.
υ	u	An empty list.