Log Message:
Update sylpheed to 3.3.0, referring PR pkg/47349.

Changes of Sylpheed

* 3.3.0

* 3.3.0rc (release candidate)

    * The Japanese manual was updated.
    * The bug that hyperlinks did not respond when 'Show attached files
      first on message view' option was set was fixed.
    * Some compilation fixes were made.
    * Win32: .eml file association was added to installer.
    * Win32: mailto and .eml association are automatically set to default
      on Windows 7 on installation.
    * Win32: included libtiff library was updated to 3.9.7 (security fix).

* 3.3.0beta2 (development)

    * The ability of opening external rfc822 format message files (.eml) was
      added.
    * Sylpheed now accepts mailto: and file: URL without command-line option.
      (sylpheed file:///path/to/file.eml)
    * The option to specify the position of the attach tool button was added.
    * The header labels on the header view now have tooltips.
    * A minor memory leak related to tooltips was fixed.
    * The long-standing drag-without-button-press bug on IMAP folders (since
      3.0) was fixed (#93).
    * The sylpheed.desktop file was modified so that desktop shells can
      recognize Sylpheed as rfc822 and mailto handler.
    * The sylpheed.spec file was fixed so that it builds on x86_64 platform,
      and also builds sylpheed-plugins package.

* 3.3.0beta1 (development)

    * Attached files are now placed first on the message view.
    * Attached files can be opened from the attachment tool menu.
    * The attachment tool menu was moved to the left of the header view.
    * The option 'Toggle attachment list view with tab' and 'Show attached
      files first on message view' were added at 'Common preferences -
      Display - Attachment'.
    * 'Export only selected messages' option was added to the message export
      dialog.
    * The import/export of messages became cancellable.
    * config.rpath and install-sh script in the tarball were updated.
    * IMAP FETCH command response parser was fixed.