Log Message:
Update sylpheed to 3.1.4.

* 3.1.4 (stable)

    * Some minor fixes for IMAP were made.
    * A bug that cancelling editing contact on address book results in
      click-and-drag behavior with newer GTK+ was fixed.
    * Corrupted message caches of news and IMAP are automatically discarded
      now.
    * Win32: included libpng library was updated to 1.2.49 (security fix).
    * Win32: included libtiff library was updated to 3.9.6 with CVE-2012-1173
      patch (security fix).
    * Win32: OpenSSL was updated to 0.9.8w (security fix).
    * Win32: the bug that the installation process continued even if uninstall
      was cancelled on update was fixed.

* 3.1.3 (stable)

    * On browsing IMAP folder, the error "imap_cmd_gen_send: cannot send
      command because another command is already running." was fixed.
    * The crash bug that occurred when IMAP message fetching and new
      message checking happened at the same time was fixed.
    * The crash bug that was caused by offline switch while IMAP session was
      active was fixed.
    * A bug that filter settings were lost if Escape key was pressed
      quickly on auto filter creation was fixed.
    * Win32: OpenSSL was updated to 0.9.8t (security fix).
    * Win32: included libpng library was updated to 1.2.47 (security fix).
    * Win32: included curl executable was updated to 7.24.0.