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- full support for unicode and other charsets, and binary input
- experimental S/MIME support via OpenSSL (API may change)
- change to LGPL license
- new create_mime function to create MIME attachments
- new mail_binary and mail_payload functions for 8bit encodings
- create_mail has new BCC and charset parameters
- valid key ids may be explicitly specified for verify and decrypt
- recipient key ids may be explicitly specified for encrypt
- support for multiple passphrases in verify/decrypt
- backwards incompatible change:
- ending renamed to linesep in protect_mail
- missing default_key no longer raises KeyMissingError
- sign=True always uses sender key
- decrypt no longer accepts default_key parameter
- pgp and transport module are no longer imported by toplevel
- use email policies for Python3 and improved Python3 support
- more coverage
- minor bugfixes