build
Centers app icon.
Adds reference to an awesome open-source project very similar to ours.
Major changes incorporating feedback from class collected Nov 25 Re Issue #7:

- Direct selection of data series (and indication of selected series) using the map. The map is basically the legend.
- Dynamic hide/unhide ability for series in the chart. When a series is deselected and then selected again it's data is simply shown again instead of being reloaded.
- Minor performance and reliability improvements.
Styles the chart.
Puts chart and map next to each other, which was the number one piece of feedback collected from class on Nov 25. Re Issue #7. Cites UNL Drought Monitor data. Updates screenshot.
builds for deploy.