class for easily plotting multidimensional data in 3 dimensions: x, y, color
This is precursor to FluCoMa's FluidPlotter class. FluidPlotter is designed for simpler interface with other FluCoMa objects, specifically FluidDataSet. PlotXYColor may still be useful to keep around because it has some additional functionality that FluidPlotter does not, such as the ability to load in datasets of an arbitrary number of dimensions and then select from a dropdown which dimensions to view.