Implement more general use of fluent interfaces in methods

[GoogleCodeExporter]

I've noticed that you are allowing fluent interfaces when, for example, 
populating the cells in a row, which makes it easy to write code such as:

$row = new Row();
$row->addCell(new Cell("Foo"))
    ->addCell(new Cell(123))
    ->addCell(new Cell(false));

It would be nice if it were possible to also write code like:

$chart = new AreaChart("somechart", $someData);
$chart->setTitle("Chart title)
      ->setLegend($legend)
      ->setIsStacked(true)
      ->setVAxis(new Axis("foobar"));

More a style thing that a core thing.

Tnxs for the great lib, btw.

Original issue reported on code.google.com by jesus.ca...@gmail.com on 14 Aug 2012 at 8:21

[GoogleCodeExporter]

I have added the fluent interface to the Row-class when almost all 
implementation was done (and it wasn't in the design either). That's why I 
haven't used it consequently.

But your right. Implementing fluent interfaces for options and maybe other 
methods would make coding easier and the design/style more consistent. 
=> I'll add it in the next release.

Original comment by patrick....@gmail.com on 15 Aug 2012 at 9:48