Log Message:
Update to 2.2.2.

* 2.2.2 (stable)

    * The crash bug that occurred when trying to move IMAP4 folders right
      under the root folder was fixed.
    * The crash bug that occurred after a message window was closed while the
      search dialog was still open was fixed.
    * Win32: The console window is newly created if --debug or --help option
      is specified.
    * Win32: The non-ASCII filename encoding problem on executing external
      commands was fixed.
    * Win32: The bug that the main window became not responsive when an error
      occurred on automatic receiving while the window was minimized was fixed.
    * Win32: Spanish translation was added for the installer.
    * Win32: The installer was fixed so that it selects correct language on
      environments other than Japanese.