Add more results / plots

[svenseeberg]

Blocked because animations do not work and heat maps for floating particles are not documented (see also #63 (comment)):

Traceback (most recent call last):
 File "/code/leeway/simulation.py", line 141, in <module>
   main()
 File "/code/leeway/simulation.py", line 120, in main
   simulation.animation(background=['x_sea_water_velocity', 'y_sea_water_velocity'],
 File "/code/opendrift/models/basemodel/__init__.py", line 2746, in animation
   self.get_map_background(ax, background, crs,
 File "/code/opendrift/models/basemodel/__init__.py", line 3748, in get_map_background
   data = reader.get_variables(background, time, reader_x, reader_y, None)
 File "/code/opendrift/readers/reader_lazy.py", line 54, in get_variables
   return self.reader.get_variables(*args, **kwargs)
 File "/code/opendrift/readers/reader_netCDF_CF_generic.py", line 330, in get_variables
   self.nearest_time(time)
 File "/code/opendrift/readers/basereader/variables.py", line 410, in nearest_time
   if (time - time_before) < (time_after - time):
 File "src/cftime/_cftime.pyx", line 1574, in cftime._cftime.datetime.__sub__
TypeError: cannot compute the time difference between dates with different calendars

[svenseeberg]

Superseded by #95