Aliases:
	from a local file, kinda like requirements.txt, maps name to hash,
	either package/module name, or an author/public key name.

Example:
from cas.a.jmg.utils import aiter, anext

Make sure that when an alias is used, that the same module is returned when a
direct hash import is used.

Local cache:
	if a directory like ~/.cas_cache exists, use it's contents automatically,
	and if it's writable, write any network fetched imported data to it.

Features:
	add:
		file
		url
		ipfs hash
		git(?)hub?

	init cache: