Update with local installation info (#484)

Co-authored-by: Kyle Barron <kylebarron2@gmail.com>

python/README.md

@@ -18,3 +18,5 @@ In order to obtain relevant modules, you should install them from PyPI directly,
 ```
 pip install geoarrow-rust-core
 ```
+
+See [DEVELOP.md](docs/DEVELOP.md) in the `docs` folder for more information on developing and building the Python bindings.

python/docs/DEVELOP.md

@@ -1,6 +1,40 @@
 # Develop Docs
 
-## Environment installation
+
+## Development
+
+To install versions of the package under active development, you need to have Rust and `maturin` installed, e.g. with:
+
+```
+rustup update stable
+pip install maturin
+```
+
+clone the repo and navigate into it:
+
+```
+git clone https://github.com/geoarrow/geoarrow-rs
+cd geoarrow-rs
+```
+
+From there navigate to the `python/core` (or other package) directory and develop with `maturin` (add the `--release` flag to the final command to build in release mode if you're benchmarking):
+
+```
+cd python/core  
+virtualenv env  
+source ./env/bin/activate  
+pip install -U maturin  
+maturin develop
+```
+
+You can also install packages locally with `pip`:
+
+```
+pip install .
+```
+
+
+## Environment installation for docs
 
 Install Python dependencies, e.g. mkdocs et al.