Improve marker styling

[Eric-Arellano]

Improvements:

• Increases marker size when you zoom in
• Differentiates no-mandates places from other places
  • red vs orange
  • no-mandates guaranteed to be on top (z-index)
  • no-mandates have 2px larger radius
• turns off zoom past level 3 (default), since it is too big to be useful and it does not render Asia correctly until you zoom to the left

Orange was chosen to be accessible for color blindness; it contrasts well with the red on grayscale.