CLI: refactor all commands to accept file list as input

apkg commands were refactored to use a list of files (as opposed to a single file) as both input and output, but CLI doesn't really allow that for options like --archive and --srcpkg.

CLI needs to be aligned to support passing a list of files as input for all commands.

Furthermore, all commands should accept input from file too, including standard input so that data can be piped between apkg commands and/or files easily.

This is a generalization and superset of #30 (closed) .

Examples:

apkg srcpkg -a foo-1.2.tar.gz foo-1.2.tar.gz.asc
apkg srcpkg -a pkg/archives/foo-1.2/*
apkg srcpkg -A archive_list_file
apkg make-archive | apkg srcpkg -A -

apkg build -s foo_1.2-1.dsc foo_1.2.orig.tar.xz foo_1.2-1.debian.tar.xz
apkg build -s pkg/srcpkgs/debian-10/foo-1.2-1/*
apkg build -a pkg/archives/foo-1.2/*
apkg build -S srcpkgs_list_file
apkg srcpkg | apkg build -S -
apkg get-archive | apkg build -A -

As this is a noticable change of CLI, it should definitely be done before %v0.1.