adding a file to git: +.ly

[Graham Percival]

In the input/* collated-files, we use a file called +.ly to display info 
at the top of the collection.  How do I escape the file to add it to 
git?  I've tried "", \, and everything else I can think of.  "git add" 
always thinks the + is a git option, not a filename char.

Here's a file I tried to add as
input/lsr/trick/+.ly

If somebody could add it for me (and also in input/lsr/advanced/+.ly ; I 
can change the text later) that would be great.



\version "2.10.0"
%% +.ly: Be the first .ly file for lys-to-tely.py.
%% Better to make lys-to-tely.py include "introduction.texi" or
%% other .texi documents too?

\header{
texidoc = #(string-append "
@section Introduction

This document shows all kinds of `tricks and tips' snippets from the
LilyPond Snippet Repository.

In the web version of this document, you can click on the file name
or figure for each example to see the corresponding input file.

This document is for LilyPond version
" (lilypond-version) ".")
}

% make sure .png  is generated.
\lyrics {  "(left blank intentionally)" }