Update scdl
add song's permalink_url in debug mode
neatly replacing json coma with \n

* need to use sed instead of tr in order not to replace comas in the title of the song
* use of \'$' for portability : sed of Mac OS X (FreeBSD version of May 10, 2005) doesn't recognise the newline escape \n (I could not make work the standard POSIX escape  : "\
", don't know why...
Merge pull request #88 from hymced/master

Correct printf: `_': invalid format character error