* Header check specifications in the `mailman.cfg` file have changed quite bit. The previous `[spam.header.foo]` sections have been removed. Instead, there's a new `[antispam]` section that contains a `header_checks` variable. This variable takes multiple lines of `Header: regexp` values, one per line. There is also a new `jump_chain` variable which names the chain to jump to should any of the header checks (including the list-specific, and programmatically added ones) match.
* Fixed a typo when returning the configuration file's header match checks. (LP: #953497)
Also:
- Remove an unused method. - Improve test coverage for mailman/app/bounces.py - 100% test coverage for mailman/chains/headers.py - Various other minor code cleanup. - Fixed the 'any' rule, which was checking a bogus metadata dictionary key.