overhaul mapper

[bbest]

Bigger picture, am thinking of overhauling the mapper to:

• Exclusively use Mollweide
  Showing data in other projections is confusing from both user experience and backend coding.
• Show input features in Mollweide
  Use leaflet::addTiles() using tile layers created by tiler. This works around the issue of leaflet:: addRasterImage() only being able to display in web Mercator projection.
• Get cell values for all input features and solution
  Either a popup window could include all these values, or the layers list in the sidebar could update with values.
• Toggle layers in the sidebar
  Want to be able to quickly toggle between features and solutions, while maintaining current zoom extent. Use radio widget for both:
  • input features
  • output scenarios