Remove obsolete tips from cvsdiffclient header.  Move the "editable" comments
together, after the instructions, to be more consistent.

Replace "review" by "inspection."

Try to find the cvs-modified-files.pl in the same place as the cvsdiffclient
if it's not in $PATH.

Make this more obvious.

Update the CVS commit script to add a reminder about HLD/DLD updates.
r=design meeting

- b1_4 is basically the parent of HEAD, because that's the direction
  that changes flow, as strange as that sounds.  so there's a
  HEAD_BASE tag which sits on b1_4