'old-relative warnings

[Erik Sandberg]

Hi,

The warnings 
foo.ly: old relative compatibility was not used.
are not very accurate. It seems that they occur iff the relative compat. was 
not used between the last occurence of
#(ly:set-option 'old-relative)
and the end of the lilypond input file.

So the problems are:
1. The following gives no warning (it should; the first set-option is 
superfluous. The problem occurs often in reality, through \include):
#(ly:set-option 'old-relative)
#(ly:set-option 'old-relative)
A = \notes \relative c'' { <<b \\ f,>> d }

2. When a warning occurs, lily does not point out where the superfluous 
relative was written.

Erik