title: How to update CorePlot Y range with animation?
body: <p>In my app, there are 100 x-points in a scatter plot, and the plot xRange length is 5, I mean only show 5 points in one screen. I want to update the yRange dynamically with an animation based on currently visible points.</p>
  
  <p>For example, the currently visible points are x: {1,2,3,4,5}, y: {15,25,35.45,55}, so the y range is <code>[CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat(15) length:CPTDecimalFromFloat(5)]</code>.
   After scrolling the plot the x values change to {8,9,10,11,12} and the y values are {100,200,300,400,500}, hence the new y range changes to <code>[CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat(100) length:CPTDecimalFromFloat(5)]</code>. Now I want this change to happen with animation. How to add animation to update the plot range?</p>