modified domain_client_validate to take trust account name / type. this

modified domain_client_validate to take trust account name / type.  this
is to pass DOMAIN_NAME$ and SEC_CHAN_DOMAIN instead of WKSTA_NAME$ and
SEC_CHAN_WKSTA.

modified check_domain_security to determine if domain name is own domain,
and to use wksta trust account if so, otherwise check "trusting domains"
parameter and use inter-domain trust account if so, otherwise return
False.
(This used to be commit 97ec74e1fa99d773812d2df402251fafb76b181c)