Figure out better ways to mark results for comparison

Right now, the 'a' and 'b' keys are used to switch between selections. Both selections would be shown in the analysis panes (FMD, histograms, etc) after the user clicks in the map.

Ideally, there would be a better interface for selection, and some sort of ability to choose polygonal areas for further analysis.

General behavior summary Currently, when you perform a calculation form the ƒ(x,y) menu, a new tab pops up with the results, and the panes are cleared out. So far, all as expected.

When you click in the results map, your click is registered at the nearest grid point. A circle is drawn at the radius used for the calculation, and the appropriate events are also highlighted. Press '?' to find out what other options are available.