Add information to body of encrypted messages
* src/mailitem-events.cpp (HTML_TEMPLATE): A message to be shown in the body of encrypted messages. Will become a template for l10n later. * src/mailitem-events.cpp (Invoke): Use the message to wipe the body. (handle_read): Use the message in case of failed decryption.
This message is whats shown for processed messages that are stored.
E.g. If you access them with another client or if gpgol is uninstalled
or deactivated.