Update changelog w/ conservative, new api.

Author: BSchilperoort

CHANGELOG.md

@@ -4,6 +4,17 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/).
 
+## Unreleased
+
+Added:
+ - xarray DataArrays are now supported
+ - A conservative regridding method has been added, along with a benchmark notebook.
+
+Changed:
+ - The API has changed. Regridding is now done with `xr.Dataset.regrid.method()`. 
+   - E.g. `xr.Dataset.regrid.linear()`
+
+
 ## v0.1.0 (2023-08-17)
 First release of `xarray-regrid`, containing:
 - the implementation of linear, nearest-neighbor and cubic regridding.