* Replaced custom smooth filter for `scipy`'s `ndimage` filter.
* Re-factor `datasets` to avoid the `basemap` syntax in favor of a `bbox` like syntax.
* Re-factor `ff_tools` into a single `ocfis` module.
* Moved `compass` to plotting.
* Added `get_gebco15` function to extract gebco15 bathymetry.
* Removed `teaching` and `smoothers` modules as they were here only for learning purposes.
* Removed `shapely` and use `matplotlib.path.Path` in `in_polygon` instead.
* Many speed improvements via lazy imports and updates.
* Re-added a re-factored version of the filters module.
* Re-factored datasets and fixed many data sources.