Add filenames for our mime parts
* src/cryptcontroller.cpp (create_sign_attach): Add file name for signatures. * src/mimemaker.cpp (create_top_encryption_header): Add file name for OpenPGP encrypted. * src/mimemaker.h: Add defines for filenames.
This makes it look nicer if a client does not support PGP/MIME
and you can even open the message with Kleopatra.
- GnuPG-Bug-Id: T4258