Adds support of multipart/related for inline attachments#181

Open

BluePsyduck wants to merge 2 commits intoemersion:masterfrom BluePsyduck:feature/inline-attachments

+174-11

Commits on Jun 15, 2024

Added new RelatedWriter to write a multipart/related part into a mail.
BluePsyduck
committed
Added AlternativeWriter replacing the InlineWriter, deprecated the latter.
BluePsyduck
committed