alexcrawford0927/cyclonetracking: v12.4.1

This release is mostly to respond to a change in how the reprojection functions used have changed. Updates were also made to how tracks results are aggregated into gridded fields. None of these updates change the number of tracks generated in the test data (557 tracks in Jan 1979 of ERA5 data at 100 km resolution and default settings -- 166 of which last more than 24 hours).

Full details 1) Reprojection functions used no longer extrapolate beyond range of input grid. Therefore, reprojection code has been updated to prevent seams developing when going from rectilinear projections to polar projections. For polar grids, cells in the opposite hemisphere are now NaN instead of being unrealistically extrapolated.

2) The aggregation scripts have been updated so that if a prior aggregation script already exists (e.g., 1979-2020), an extra year of data (e.g., 2021) will be appended to the pre-existing netcdf instead of re-processing all years.

3) Climatology calculations of aggregated fields have been moved to a separate script.

4) A regional mask I often use is now available as a netCDF file on the associated Google Drive.

5) A bug in the 360-day calendar in the timeAdd function has been fixed.