fixing edit section bugs

  - Final edit section now ignored when there is only one header.
  - The configuration property 'maxseclevel' is now honored again.
    - Instructions are not created by the handler for edit sections
      that have a level higher than 'maxseclevel'. These ignored
      edit sections are merged into the previous edit section.

darcs-hash:20060617223723-05dcb-a1282e827468de00977179c8c8924fb00ec2d56c.gz