This patch adds more tests for the dovecot library, in particular:
- Protocol errors (invalid versions, etc.).
- Invalid command (cli-specific test).
- Connection breakups.
This patch adds a missing docstrings for exported identifiers, and
adjust some of the existing ones to match the standard style.
In some cases, the identifiers were un-exported after noticing they had
no external users.
Besides improving documentation, it also reduces the linter noise
significantly.
This patch adds a new package which implements two basic primitives for
authenticating against dovecot ("user exists", and "check password").
It is still experimental/work in progress.
