GSoC 2016 - GNU website listing

[Paul Morris]

So students can find us as one of the GNU projects, we should get LilyPond 
listed on the GNU GSoC suggestions page.  Here’s the one for last summer:  
http://www.gnu.org/software/soc-projects/ideas-2015.html

Seems we should just have a listing like those that point to external webpages, 
like this:

LilyPond maintains their list of ideas for GSOC in an external webpage: 
http://lilypond.org/google-summer-of-code.html 
<http://lilypond.org/google-summer-of-code.html>


Possibly we could add a description like this (from the 2012 GNU GSoC page):

LilyPond is a music engraving program, devoted to producing the highest-quality 
sheet music possible. It is somewhat similar to TeX — the user describes the 
music using a high level description input, which is processed with LilyPond to 
produce a pdf file. Languages used: mostly C++, Scheme and Python.  

-Paul