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.
Use the SC_VERSION autoconf macro

Conflicts:
	sc
Revert to ax_prefix_config.m4
Remove restrict keywords
Edits on comments in p4est_lnodes.h
Move extern C into proper place
test of degenerate case of lnodes
started work on extending iterate

- execute at indirectly touched entities
- provide more information at corners/edges
  this should allow lnodes to simplify a lot once it's done
Added p4est_iterate_ext
some documentation for the new faces/edges fields of side info in p4est_iterate.
Merge branch 'test-lnodes' into iterate-ext
cleaned up the control-flow in iterate
iterate: fix bug in determining cside faces
iterate: sort intertree inputs, so lowest is always first
lnodes simplification