Added axis titles and animation to the x-axis label.

A couple of questions when making this update:

1. When using the ternary operator continue does not seem to work whithin a for loop. line 43 of index.js

2. Need to call the plot() function before i is incremented. Is this related to the fact that this is an async function? So will i only be evaluated within call() and not when the scatterPlot() instance is created? line 65 of index.js