[translations] not translating a node in a file

[Federico Bruni <fede@xxxxxxxxxxxxx>]

Hi translators

Continuous changes to Google Summer of Code node made me think about 
removing the translation, because maintaining the translation is too 
cumbersome and it's not worth (as any GSoC candidate should speak 
english).
The problem is that I do not want to throw away all the community 
italian file, of course.

The documentation seems to suggest that something like this:

"""
@node Google Summer of Code
@unnumberedsec Google Summer of Code
@translationof Google Summer of Code

@untranslated
"""

should load the text from the original english file into the localized 
page.
Ok, probably it's just my imagination. I've found it here:
http://lilypond.org/doc/v2.19/Documentation/contributor/documentation-translation-details#translating-the-web-site-and-other-texinfo-documentation

When I run "make website" after applying above change I get a 404 error 
when I try to open the italian GSoC page.
So the italian node is not created.
It's a bug or I'm missing something? (see patch attached if you want to 
try it out)

An alternative might be moving the GSoC page in an includable file (in 
Documentation/included/), so we can easily include the english text in 
a localized website.

Thanks for any suggestion
Federico