0.24 (04/02/2009)
    (ms) Added support for capturing PRINT output as suggested by
         Peter Mistich. print_output() now returns a ref to an array
         with the output of the last graph() command's PRINT output.

0.23 (02/05/2009)
    (ms) update() now accepts DateTime objects as well (suggested by 
         Jay Buffington)
    (ms) [rt.cpan.org #43011] Fixed rounding error on 64-bit systems
         reported by Todd E. Rinaldo

0.22 (05/20/2008)
    (ms) Added aberrant behavior detection (hwpredict) with documentation
         and test cases.

0.21 (01/23/2008)
    (ms) Provided backwards compatibility to rrdtool-1.0 for 
         draw/type=stack, which now translates to an area with the 
         :STACK option.

0.20 (01/22/2008)
    (ms) Bas van der Veen reported that the rrdtool download link 
         changed to http://oss.oetiker.ch/rrdtool/pub/rrdtool.tar.gz,
         adapted Makefile.PL.
    (ms) No longer expecting 'Permission denied' to support localized
         OSes.

0.19 (05/12/2007)
    (ms) Added 'strict' mode (defaults to true).
    (ms) Added latest graph parameters from the latest rrdtool release.

0.18 (05/12/2007)
    (ms) Added 'dry mode' patch by Jacquelin Charbonnel.

0.17 (09/10/2006)
    (ms) Changed build command in Makefile.PL to adapt to new
         rrdtool-1.2 directory hierarchy, as suggested by Zac Israel.

0.16 (08/23/2006)
    (ms) Added 'base' option to graph method, as suggested by 
         Anton Shevchenko.

0.15 (07/23/2006)
    (ms) Fixed bug with multiple comment lines, of which only the first
         one was printed in the graph. It was introduced in 0.14. 
         Thanks to Steve van der Burg for reporting and a patch.

0.14 (04/28/2006)
    (ms) Order of prints, legends, gprints etc. now preserved, see
         http://lists.ee.ethz.ch/rrd-users/msg11161.html

0.13 (08/07/2005)
    (ms) Added line, area, tick, and shift to graph method.
    (ms) Added vdef to graph.
    (ms) More checks on rrdtool installation, now requiring 1.2.x.

0.12 (07/07/2005)
    (ms) Steve van der Burg added vrule, comment, and font options
    (ms) Makefile.PL dependencies version number changed from undef to 0
    (ms) Added 'rigid' option to graph.

0.11 (01/05/2005)
    (ms) Added suggestion by Richard Lippmann <lippmann@sprachtheorie.de>
         to allow for invisible graphs, just used as base for later 
         'cdef' calculations. Since leaving 'type' out will have
         RRDTool::OO default to 'line', type => 'hidden' is used to
         indicate the graph shouldn't be drawn. 
    (ms) Added gprint/print options for graphs

0.10 (11/20/2004)
    (ms) Added legends to graph()
    (ms) Maxence Gerbedoen <maxxenceg@wanadoo.fr> suggested a patch to 
         add 'cdef' functionality. Added slightly differently.

0.09 (10/08/2004)
    (ms) Fixed bug [cpan #7897]. new() now accepts a raise_error setting.

0.08 (09/24/2004)
    (ms) Added documentation for multiple data sources and archives.
    (ms) Martin Kurahaupo <martin@kurahaupo.gen.nz> added a patch
         to prevent the test suite from failing when run as root
         because a test file can't be write-protected.
    (ms) Chris Fedde <cfedde@denver.pm.org> provided a patch to 
         structure ::info's output more perl-like. Got input from
         perlmonks (thanks nobull!) on how to efficiently transform
         RRDTools info output into Perl data structures.

0.07 (08/15/2004)
    (ms) doc and test fixes for new rrdtool release 1.0.49. dump()
         and restore() are now supported.

0.06 (06/21/2004)
    (ms) added 'start' param in create() docs
    (ms) JJ Knitis <jj@dangercreative.com> provided a fix for
         multiple 'color' settings in graph. Added new graph/color
         syntax.

0.05 (05/26/2004)
    (ms) added support for dump() and restore(). Test cases in
         t/007Dump.t will wait until these functions are 
         available in rrdtool, and are skipped until then.
    (ms) Some graph options don't have parameters, they can
         specified via option_name => undef now.
    (ms) Added lower_limit graph option
    (ms) Added eg/graph.pl as a graph example

0.04 05/22/2004
    (ms) added more functionality to graph(), new test cases.
    (ms) if a graph contains several files, use the defaults
         from each file
    (ms) added tune(), info(), last().
         dump()/restore() added also, but not activated yet, 
         because not available via RRDs.

0.03 05/18/2004
    (ms) fixed discovery of CFs
    (ms) fixed update with values/hash and added test case

0.02 05/16/2004
    (ms) used rrdtool info for meta queries

0.01 05/12/2004
    (ms) Where it all began.

TODO:

* fetch_start/next iterator with saved timestamp, without caching all values
