0.36  (05/12/2015)
    (ms) Gelu Lupa added RRD's first() function.

0.35  (07/20/2014)
    (ms) Fix for [rt.cpan.org #97322], now rounding results to cope with
         floating point inaccuracies in rrdtool. Reported by Andreas König.

0.34  (06/26/2014)
    (ms) Added disable_rrdtool_tag option as suggested by Sun Guonian.

0.33  (07/08/2013)
    (ms) Florian Eckert reported that graph() modified 2nd level
         entries of the options array passed to it. Used Storable::clone
         in OO.pm to make a deep copy first.

0.32  (03/06/2012)
    (ms) [rt.cpan.org #63351] Applied modified patch by Jonas Wagner to
         fix stacked graphs with no legend.
    (ms) Implements RRDs::xport and returns a Perl structure instead of 
         basic xport array (Remi Ferrand, Fabien Wernli).

0.31  (05/26/2010)
    (ms) [rt.cpan.org #54870] Fixed typos/pod errors reported by
         Salvatore Bonaccorso.
    (ms) Fixed overwriting input parameters in create(), bug reported
         by Erik Wasser.

0.30  (02/21/2010)
    (ms) [RT 53961] Worked around rrdtool-1.3.5 inaccuracy problem by
         skipping certain tests for rrdtool <= 1.4.

0.29  (02/20/2010)
    (ms) Added github repository link to Makefile.PL
    (ms) Fixed documentation for fetch_next().
    (ms) [RT 54544] Tom Regner added support for updatev().

0.28 (11/05/2009)
    (ms) Applied patch by Lyle Brooks, adding optional step, start, and
         end parameters to "draw".

0.27 (10/11/2009)
    (ms) Slaven Rezic reported huge memory consumption by the test suite,
         turned out to be fetch_start() call spanning several years. 
         Fixed by defining the end time as well as the start time.

0.26 (09/27/2009)
    (ms) [RT 32601] Using prompt() instead of manually asking for input 
         in Makefile.PL (by Fabien Wernli)
    (ms) [RT 32046] Calling setlocale() to fix error message check in 
         foreign locales (by Fabien Wernli)
    (ms) Implemented graphv method. This works just like graph() but uses 
         rrdtool's graphv internally, giving access to additional 
         information using print_results() method (by Fabien Wernli)
    (ms) Improved RRDs version testing (by Fabien Wernli).

0.25 (04/25/2009)
    (ms) Applied patch by Christian Dengler, adding the 'hrule' graph
         parameter and increasing the sleep time in 002Pod.t to two
         secs to prevent system clock inacurracies from causing
         test failures.

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