Hometown grouping

[SnoopJ]

Since casualties may come from the same hometown (notably Baltimore City with a massive 415 casualties), it makes more sense for each circle entity to represent any number of casualties, with the number being represented shown to the user by some other means (size of circle, fill color, etc.)

Basic demonstration of this is implemented in ad84d08, but some issues need to be addressed:

• Need to display how many casualties each circle represents in an intuitive way.
• Need to be able to navigate casualties for each circle
• Filters may need adjustment to work with this (need to test them!)
• The few hometown/county mixups may throw a monkey-wrench into this

There are also a few casualties who have a hometown set, but are listed as county unknown (999), which creates a separate circle.