Don't install slocate by default on Desktops

Binary package hint: slocate

(Discussed here: https://lists.ubuntu.com/archives/ubuntu-devel-discuss/2007-September/001646.html)

The slocate cron.daily job has long been an issue, making users ask why their computers were not responding or simply working hard without any explanation. This little 'bug' is giving a really bad impression to new users, making Ubuntu look 'Windows-like' (the worst for us), that is to say unstable and strange.

Having a look to Launchpad bug tracker, you can see that at least 5 open bugs refer to this problem, some proposing patches to make the issue less annoying. Those are:
Bug 134692 (with a committed patch, about using ionice to lessen the io usage of updatedb)
Bug 13671 (duplicate*, reporting ionice issues making previous patch almost unefficient)
Bug 133638 (about telling the user that the system is indexing files)
Bug 41742 (about a laptop not wanting to suspend when updatedb has automatically started)

And partly those, because bugs with slocate affect out-of-the-box users
that don't really need it:
Bug 113312 (about encrypted partition being indexed without notice from a newbie user)
Bug 74029 (about /mnt default indexation issues)

This bug should really be rapidly considered and solves by choosing a clear policy for Ubuntu. If we really want to keep the locate command working out-of-the-box in Ubuntu, we should find out ways of making updatedb run : 1) with low io and CPU priority 2) only when the user is not using his computer (just like Tracker will be doing by default in Gutsy).

Or we can consider using rlocate (http://rlocate.sourceforge.net/), which is a synchronized replacement for locate, keeping track of the filesystem updates when they are done.

We can also think (and this is my opinion ;-) ) that the locate command is only used by advanced users that know how to install slocate in two minutes, and thus that we don't need to install it by default. Newbies don't use locate in a terminal, but Tracker in GNOME. And we should remember that users are likely to use new background processes with Tracker or Beagle, that may even be installed by default. So the less are running, the better the system will work. Replacements like find can be used when necessary (eg for occasional remote help), though they are less efficient.