...by changing the parent of SwSendMailDialog.

The destruction of the main dialog (SwMMResultEmailDialog) also
closes the progress dlg (SwSendMailDialog), which shuts down the
dispatcher stopping anymore messages from being sent. Have changed
the parent of progress dlg such that it will not close when the
main dialog is closed. This has allowed the main dialog to be
closed immediately after the progress dialog had been created
making for a cleaner ui.

There were problems with the timer causing LO to consistently crash
during the dispose of OutputDevice, but I could find no logical
reason for the crashes.
(It didn't crash if smtp authentication failed. It also didn't
crash when run in gdb...)
Moving the exit code from StateChanged to CloseHdl magically
fixed the crashing problem. I think it makes it a bit clearer
to end in closeHdl anyway, and start the timer only in case of
an early cancellation (before all the mail messages
have been queued up). This eliminates MOST of the use of the
timer - since the typical exit occurs after the email process
has finished.

Change-Id: Icd3af372772fab3e78eb0702b120d7a811baa6bd
Reviewed-on: https://gerrit.libreoffice.org/41519Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Justin Luth <justin_luth@sil.org>
Reviewed-by: Thorsten Behrens <Thorsten.Behrens@CIB.de>