Doc: NR 1.6.3 - edit eg.s in quoting other voices (issue4518053)

[percival . music . ca]

http://codereview.appspot.com/4518053/diff/1/Documentation/notation/staff.itely
File Documentation/notation/staff.itely (right):

http://codereview.appspot.com/4518053/diff/1/Documentation/notation/staff.itely#newcode1022
Documentation/notation/staff.itely:1022: @cindex quote, voices
could we keep the old @cindex as well?  I'm fine with adding the new
ones; just don't remove the old ones.

http://codereview.appspot.com/4518053/diff/1/Documentation/notation/staff.itely#newcode1045
Documentation/notation/staff.itely:1045: \addQuote "flute" @{
\fluteNotes @}
could we keep a definition for \fluteNotes ?  again, I'm happy to have
the name change, but I'd like to see some notes actually being defined.

alternately, remove the @example and just go directly into the
@lilypond.  That would be my first instinct, actually, although I can't
claim to have looked at this in detail.

http://codereview.appspot.com/4518053/