Scatterplot with points indexes

Like standard scatterplot() function but adds indexes of the data points.

Unlike standard scatterplot() which doesn't allow you to plot on the current figure, this function works in a more conventional way (e.g. similar to plot()) and allows you to specify also a title string and the plot string (colour, marker).
More important, it adds indexes of the plotted data samples next to each sample, making it easier to debug small data sets scatter-plotted.