The mail library implements everything that is needed for being used to
implement a mail reader (MUA).
It therefor provides reading mailboxes, getting related content or mails, saving
attachments to external locations, crafting new mails and responses,...
It also offers, natively, ways to search for mails (which are represented as
imag entries).
For more information on the domain of the `imag-mail` command, look at the
documentation of the @sec:modules:mails module.