Use this function instead of plot_ly() to initialize
a plotly-mapbox object. This enforces the entire plot so use
the scattermapbox trace type, and enables higher level geometries
like add_polygons() to work
plot_mapbox(data = data.frame(), ...)A data frame (optional).
arguments passed along to plot_ly(). They should be
valid scattermapbox attributes - https://plotly.com/r/reference/#scattermapbox.
Note that x/y can also be used in place of lat/lon.