r22704: Implement three step method for enumerating domain trusts.
(a) Query our primary domain for trusts
(b) Query all tree roots in our forest
(c) Query all forest roots in trusted forests.
This will give us a complete trust topology including
domains via transitive Krb5 trusts. We also store the
trust type, flags, and attributes so we can determine
one-way trusted domains (outgoing only trust path).
Patch for one-way trusts coming in a later check-in.
"wbinfo -m" now lists all domains in the domain_list() as held
by the main winbindd process.
(This used to be commit
9cf6068f1e0a1063d331af17aa493140497b96ef)