feat(db-remove): revamp arguments to handle all arches in one batch

This effectively also fixes multiple issues with combinations of any
packages and their native subset removal. The sacrifice is a different
CLI interface that caller need to adapt to.

For specific use cases a new --arch options has been introduced to just
remove a specific architecture.

For removing only partial packages from a split pkgbase, the option
--partial must be passed. By default only allow removing complete
pkgbase. This makes both operation mutual and explicit, either remove
partial packages or remove complete pkgbases.

Fixes #21
Fixes #39