Add cost_distance to README feature matrix

Author: brendancol

README.md

@@ -192,6 +192,7 @@ In the GIS world, rasters are used for representing continuous phenomena (e.g. e
 | Name | Description | NumPy xr.DataArray | Dask xr.DataArray | CuPy GPU xr.DataArray | Dask GPU xr.DataArray |
 |:----------:|:------------|:----------------------:|:--------------------:|:-------------------:|:------:|
 | [Allocation](xrspatial/proximity.py) | Assigns each cell to the identity of the nearest source feature | ✅️ | ✅ | | |
+| [Cost Distance](xrspatial/cost_distance.py) | Computes minimum accumulated cost to the nearest source through a friction surface | ✅️ | ✅ | | |
 | [Direction](xrspatial/proximity.py) | Computes the direction from each cell to the nearest source feature | ✅️ | ✅ | | |
 | [Proximity](xrspatial/proximity.py) | Computes the distance from each cell to the nearest source feature | ✅️ | ✅ | | |