[collectd] CSV plugin

[Christophe Kalt]

Arg.. i'll never complete the migration to v4.x
It's been such a painful and lengthy process that i need to
rant/vent a bit, sorry.  (skip the next 2 paragraphs;)

The latest round of pain has been the fact that data that
belongs together has been spread around various files for no
obvious reason (at least to me).  (I'm curious to hear why,
btw)

There's also no apprent consistency.  The load plugin keeps it
all in one file, but the cpu plugin doesn't.  And then, the df
plugin keeps it all in one file per filesystem, and all of
these within a single directory, while the cpu plugin has a
directory per cpu.

May be that makes more sense when outputing RRD files, but
it's definitely a pain with the CSV plugin.  On top of this, i
now find that the epoch used for each file may vary:

$ egrep '^120396949' *
swap-free-2008-02-25    :1203969496,20311580672.000000
swap-reserved-2008-02-25:1203969496,4972544.000000
swap-used-2008-02-25    :1203969495,59842560.000000
                                  ^

Excuse me?  The values all come from a single sample.
How am i supposed to merge them back together?  Any way i
could convince you to fix this particular discrepency within
collectd?  Please?