Tidied up option processing in smbclient - usage message now actually

Tidied up option processing in smbclient - usage message now actually
reflects the real options. Removed '-S' option - couldn't see what
this was doing (seemed to have something to do with nt_domain_logon ?).
Luke please check if you needed this code (code is only #ifdef'ed out
and can be re-instated).
Did this to make writing of yodl smbclient man page possible :-).
Jeremy.
(This used to be commit 97a14db75634b09dd272e9f59bc39c2b1eb52544)