plot_routes() stay color reflects departure instead of arrival date for stay #210
Description
@bmvandoren observed that the color of the stay length dots produced by plot_routes() corresponds to the date that the bird departed the stay location and not the arrival date as he expected.
Fix this by making the dot color correspond to the date of arrival for the stay.
BUT do not to break animate_routes() which wraps plot_routes(). animate_routes() shows the stay length dot gradually changing color and getting bigger as the stay progresses and ends with the final size and the color at the end of the stay. Choices made within plot_routes() to support animate_routes() are likely the source of this problem. The current behavior of animate_routes() makes sense to me. @bmvandoren does that sound right to you?
