lilypond-invoke-editor runs twice (2.19.82)

[Aaron Hill]

While getting point-and-click working in my setup, I ran across this 
minor issue.

After installation, there are two `lilypond-invoke-editor` files:

/usr/local/bin/lilypond-invoke-editor
/usr/local/lilypond/usr/bin/lilypond-invoke-editor

The first is a simple script that sets some environment and invokes the 
LilyPond version of Guile with the second file, which is the actual 
Scheme program.  The script uses the `-e main` option which causes Guile 
to invoke the named function; however, there is already an explicit 
invocation of `main` at the end of the Scheme program.  This results in 
the functionality running twice.

I suppose that, depending on how you have your EDITOR or LYEDITOR 
variables configured, you might not notice a double launch; but I was 
certainly confused at first why I was getting repeated behavior.

-- Aaron Hill