Rioxarray

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- REF: Reduce pyproj.CRS internal usage for speed (issue 241)
- ENH: Add `rioxarray.set_options` to disable exporting CRS CF grid mapping (issue 241)
- BUG: Handle merging 2D DataArray (discussion 244)

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- ENH: Added `rio.estimate_utm_crs` (issue 181)
- ENH: Add support for merging datasets with different CRS (issue 173)
- ENH: Add support for using dask in `rio.to_raster` (issue 9, pull 219, pull 223)
- ENH: Use the list version of `transform_geom` with rasterio 1.2+ (issue 180)
- ENH: Support driver autodetection with rasterio 1.2+ (issue 180)
- ENH: Allow multithreaded, lockless reads with `rioxarray.open_rasterio` (issue 214)
- ENH: Add support to clip from disk (issue 115)
- BUG: Allow `rio.write_crs` when spatial dimensions not found (pull 186)
- BUG: Update to support rasterio 1.2+ merge (issue 180)

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- BUG: Check all CRS are the same in the dataset in crs() method

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- BUG: Ensure transform correct in rio.clip without coords (pull 165)
- BUG: Ensure the nodata value matches the dtype (pull 166)
- Raise deprecation exception in add_spatial_ref and add_xy_grid_meta (pull 168)

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- Deprecate add_spatial_ref and fix warning for add_xy_grid_meta (pull 158)

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- BUG: Fix assigning fill value in `rio.pad_box` (pull 140)
- ENH: Add `rio.write_transform` to store cache in GDAL location (issue 129 & 139)
- ENH: Use rasterio windows for `rio.clip_box` (issue 142)
- BUG: Add support for negative indexes in rio.isel_window (pull 145)
- BUG: Write transform based on window in rio.isel_window (pull 145)
- ENH: Add `rio.count`, `rio.slice_xy()`, `rio.bounds()`, `rio.resolution()`, `rio.transform_bounds()` to Dataset level
- ENH: Add `rio.write_coordinate_system()` (issue 147)
- ENH: Search CF coordinate metadata to find coordinates (issue 147)
- ENH: Default `rio.clip` to assume geometry has CRS of dataset (pull 150)
- ENH: Add `rio.grid_mapping` and `rio.write_grid_mapping` & preserve original grid mapping (pull 151)