Import/export tides

[kylecorry31]

Use this format (XML):

https://api.tidesandcurrents.noaa.gov/api/prod/responseHelp.html

https://api.tidesandcurrents.noaa.gov/api/prod/datagetter?begin_date=20130808%2015:00&end_date=20130809%2015:06&station=8454000&product=high_low&units=metric&time_zone=gmt&application=ports_screen&format=xml&datum=MSL

Build a website to download these files (for US only)

If the location is equal to an existing tide, ask the user if they want to add the tides as references there (a list picker if there are multiple matches).

If a time is equal to an existing time, don't add it.

Let the user choose to export the following:

• [ ] Tide table (times)
• [ ] Tide harmonics