Ftp tweaks

Some followups from the previous pull request.
Note that, I pushed a new tag (https://github.com/mozilla/r2d2b2g/releases/tag/6.0pre4) associated to the set of xpis I released on ftp (https://ftp.mozilla.org/pub/mozilla.org/labs/fxos-simulator/1.2/)

Am I doing it right?!