Document things in README for new update

[tylerlum]

• Instructions about the csv file inputs and outputs (how to pass in inputs, when outputs are generated and where, etc)
• Instructions for passing in a custom grib with -g or what happens if you don't (creates new data.grb file and uses that)
• Detailed info about what should be passed into the code and how to run the big while loop (run ./runpathfinder, how long it typically takes, how to use network table vs. coordinates, what happens if network table connection not made or gps not found on table)
• Details about printing nth coordinate)
• Trim all the useless stuff (at least, put it somewhere else OR delete)
• In README: cut out land/waves, move setup to different .md file, move linting and tests and contributing and problems to a details .md, and replace with these more important documentation, probably some example pictures, lots of example code (commands to run to get different outputs, files to change to get differnet results, where files will be created)

[tylerlum]

Also about how the planner works, which files are most important, and how planet size and csvs work

[tylerlum]

Resolved, with some TODOs left in the README