Include better explanation of what this report is for in the comments.
Comment to expound more on what it means for  <Adjustment> entries to be ignored by these reports.

Loïc Dachary <loic@dachary.org>, during patch review, pondered whether the
ignoring of <Adjustment> by these scripts could ever be used to hide funds,
ala the movies Superman III and Office Space.

After discussion, we both concluded that it would not be possible to hide
funds merely with this report.  Such hiding would have to also dig into the
main Ledger codebase and muck with how it handles auto-generated <Adjustment>
entries.