samba_kcc NTDSConnection translation
This is an advancement of samba_kcc to compute and
commit the modification of a repsFrom on an NC Replica.
The repsFrom is computed according to the MS tech spec
for implied replicas of NTDSConnections. Proper maintenance
of (DRS options, schedules, etc) from a NTDSConnection are now
all present. New classes for inter-site transports, sites,
and repsFrom) are now present in kcc_utils.py. Substantively
this gets intra-site topology generation functional by committing
the repsFrom that were computed from the DSA graph implemented in
prior drops of samba_kcc
Signed-off-by: Andrew Tridgell <tridge@samba.org>