PostfixAdmin Files

Postfixadmin 4.0.1

• Add TOTP (Time based One Time Password) support (with IP based exceptions) for mailboxes, along with Application Specific Passwords ( see [#753] )
• Remove (most) requirements for using 'doveadm pw' for password hashing ( see [#491] )
• Add OpenDKIM domain key handling ( see [#631] )
• Add content security policy http headers and improve PHP session cookie security ( [#903] and [#905] )
• Updates various libraries, and moves to use 'composer' for their management (see composer.json)
• Improve unit test coverage + updates github actions build
• Various vacation.pl script improvements ( [#648], [#784], [#482], [#483] and [#495] )
• Dark theme support ( see [#569] )
• Documentation improvements
• Remove support for the MySQL ENCRYPT hashing backend (no longer supported by MySQL after 5.7)
• Various code improvements (PHP type hints, cleanups)
• Improves setup.php output (warnings/errors)
• Fix up DB migration and try to ensure MySQL tables have been migrated to InnoDB before running upgrade 1848
• Moves minimum PHP version to 7.4

There was a 4.0 release, but it somehow didn't get out of draft before @cboltz found a few minor issues, so 4.0.1 is the first v4 release.

Thank you to everyone who has contributed.