New features and changes in tin-1.7

Changes
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. interactive mailer can now be fed with headers. The old use_mailreader_i
  config variable is obsolete and superseded by the new interactive_mailer
  variable that can have three values:
  0  no interactive mailreader (old use_mailreader_i=OFF)
  1  interactive mailreader with headers
  2  interactive mailreader without headers (old use_mailreader_i=ON)

New features
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. You can now specify a mailbox folder to save your sent mails so you
  possibly don't need auto_cc or auto_bcc anymore. See tin(5).

. x_headers can take a command which generates the header(s). See tin(5).

Retired Features
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. AmigaOS support
