Update the hurricane path to be a comet

[lindsayplatt]

Previous critiques of the old path was that it looked like a crack in someone's screen, especially on mobile devices. This adjusts the storm path to be dynamic for each timestep (which makes it look like it has a comet tail) rather than a solid line for the whole animation.

This PR also adjusts the Google font issue (where you forget to load it in a new session, build all your frames with a lame font, and then go "oh crap") by loading the font at session startup through a .Rprofile file.

Updated (see the "cracked screen" version here):

[lindsayplatt]

I have tested that functionality before (in this branch), but not with these new changes. Although, now after looking at that, I think there are some differences in 1_fetch.yml. I'll add some changes to handle that case in the master branch.

[lindsayplatt]

OK, so pulled over the required changes and when you comment out storm_code and stn_event in viz_config.yml, the storm line, storm point, and subsequent legend entries are removed.

With storm_code and stn_event:

Without storm_code and stn_event:

[jordansread]

nice!

[lindsayplatt]

are we calling this 👍 for now?

[jordansread]

I think so, yes