Greyed out notes do produce output, which means that their counters need

Greyed out notes do produce output, which means that their counters need
to be treated as part of the document. For example, the footnote numbers
in LyX are wrong prior to this patch.

This will also affect word and character count, but should not affect
anything else. If that seems wrong, we can either (a) explicitly exclude
notes from the word count or else (b) introduce
  bool countWordsInInset() const;
and call that, instead.

git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@36976 a592a061-630c-0410-9148-cb99ea01b6c8