Changelog:
==========
- Fixed typo 'marking' instead of 'marketing' in case-insensitive mailbox name list.
- When DNS-based deliverability checks fail, in some cases exceptions are now
thrown with raise ... from for better nested exception tracking.
- Fixed tests to work when no local resolver can be configured.
- This project is now licensed under the Unlicense (instead of CC0).
- Minor improvements to tests.
- Minor improvements to code style.
License-Update: Relicense under the Unlicense (instead of CC0)
Signed-off-by: Wang Mingyu <wangmy@fujitsu.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>
