Adding the same changes to HEAD as were added to BRANCH_1_9_18.

Adding the same changes to HEAD as were added to BRANCH_1_9_18.

Changed smbpasswd to be client-server for a normal user, rather
than accessing the private/smbpasswd file directly (it still accesses
this file directly when run as root, so root can add users/change a
users password without knowing the old password).

A shakeout of this change is that smbpasswd can now be used to
change a users password on a remote NT machine (yep - you heard
that one right - we can now change a NT password from UNIX !!!!!).

Jeremy.