Timeline Style Options Helper
styleOptions(radius = 3, color = NULL, stroke = TRUE, fill = TRUE,
fillColor = NULL, fillOpacity = NULL)number to specify radius of drawn circle.
valid CSS color the circle.
fill and/or stroke will
override color.
logical to determine if drawn will be filled with color.
number between 0 and 1 to set opacity of the drawn circle.
list with options to style the timeline