Bug#771587: revert 0002_dont-start-desktop-outside-of-MATE-sessions.patch

[Christoph Fritz]

The intended fix 0002_dont-start-desktop-outside-of-MATE-sessions.patch
breaks documented usage of caja and is wrong! Please read the manpage
and revert this patch.

The correct fix for the issuer its problem is already described in the
manpage section EXAMPLES:

   caja --no-desktop /home/user/
        Open  a  Caja  window in "user's" home directory without
        managing the desktop.

Caja is derived from nautilus which has the same behavior: Manage the
desktop by default.

I hope you will not cripple nautilus too because it behaves in another
way as you expected.