release build failed; musicxml zip

[Graham Percival]

Reinhold posted this a few days ago, but I'm trying to restart the
discussion.  Attempting to build the 2.12.1 release fails when
creating the zip file of the musicxml regression tests.

I don't know whether to bug Reinhold for doing musicxml, John for
being one of the few people who somewhat understands the build
process, Jan for writing gub3, or Han-Wen by default.


I get a bunch of warnings like:
----
        zip warning: name not matched: 01a-Pitches-Pitches.xml
----
and then:
----
zip error: Nothing to do! (try: zip -r -9 -r
out-www/MusicXML-TestSuite-0.1.zip . -i 01a-Pitches-Pitches.xml
01b-Pitches-Intervals.xml
...
----

Reinhold suggested that the problem was "the makefile rule to
create that .zip file breaks for builddir!=srcdir", but I think
this got lost in the 2.12 chitchat:
http://lists.gnu.org/archive/html/lilypond-devel/2008-12/msg00553.html

Cheers,
- Graham