Adding support for new XYDataset and XYZDataset charts.

* Adding support for and a XML reader for XYDataset and XYZDataset, e.g.
&lt;XYZDataset&gt;
&lt;Series name="S1"&gt;&lt;Item&gt;&lt;X&gt;1.5&lt;/X&gt;&lt;Y&gt;2.5&lt;/Y&gt;&lt;Z&gt;0.25&lt;/Z&gt;&lt;/Item&gt;&lt;/Series&gt;&lt;/XYZDataset&gt;
* Adding new charts based on XYDataset and XYZDataset: ScatterPlot, XYAreaChart, XYBarChart, XYLineChart, BubbleChart.
* Adding new configuration options: foregroundAlpha, rangeLowerMargin, rangeUpperMargin, domainLowerMargin (NumberAxis only), domainUpperMargin (NumberAxis only), domainLowerBound (NumberAxis only), domainUpperBound (NumberAxis only), rangeAutoRangeIncludesZero, domainAutoRangeIncludesZero (NumberAxis only), rangeZeroBaselineVisible, domainZeroBaselineVisible (NumberAxis only), rangeIntegerTickUnits, domainIntegerTickUnits (NumberAxis only), rangeGridlinesVisible, domainGridlinesVisible, and for Scatter plot: dotHeight, dotWidth.