connectivity_is_equivalent: compare fields, not bytes.
bits: added nface argument to face_neighbor_extra
bits: added nedges arg to edge_neighbor_extra
bits: added ncorners to p4est_corner_neighbor_extra
bits: fixes to the recent neighbor_extra changes.

test_iterate: fix corner_neighbor_extra call
comm: added p4est_comm_is_owner

comm: fix to p4est_comm_is_owner.
Update libsc
Merge remote-tracking branch 'toby/hotfix-conn-equivalent' into develop