🎨 Add figure showing zen3geo composable DataPipes for geospatial (#9)

* 🎨 Add figure showing zen3geo composable DataPipes for geospatial

Illustration of zen3geo's chainable I/O readers and processors for geospatial data, designed to be ready for multi-sensor/multi-modal architectures!

Flowchart in the middle row shows STAC, vector, raster, spatial and other DataPipes making up zen3geo. Bottom row shows some of the key features of zen3geo (as of v0.6.2), and a future roadmap.

Also added logos for GeoPackage and NetCDF to the list in figures/README.md.

* ➕ Add python-graphviz

Simple Python interface for Graphviz! Repo at https://github.com/xflr6/graphviz

* 🎨 Add figure showing demo code of a zen3geo DataPipe

Illustration of a zen3geo DataPipe from a Zarr store to Pytorch tensors. Code is shown on the left, and a graphviz plot is shown on the right, with blue arrows annotated with comments showing what each code line is doing. Also linking to full presentation slides on https://hackmd.io/@weiji14/foss4g2023oceania

README.md

@@ -39,6 +39,11 @@ with the [Pangeo ML Working Group](https://pangeo.io/meeting-notes.html#working-
 
 [![NVIDIA GPUDirect Storage schematic](https://github.com/weiji14/foss4g2023oceania/assets/23487320/b339605a-492b-4c5c-8a06-b14ebcd258b7)](https://github.com/weiji14/foss4g2023oceania/pull/6)
 [![xbatcher n-dimensional slicing](https://github.com/weiji14/foss4g2023oceania/assets/23487320/38af26ca-83ea-4798-be7f-95608ad56df0)](https://github.com/weiji14/foss4g2023oceania/pull/8)
+[![zen3geo Composable DataPipes](https://github.com/weiji14/foss4g2023oceania/assets/23487320/d6530fbd-3f83-4b50-a73b-5a1b696158bf)](https://github.com/weiji14/foss4g2023oceania/pull/9)
+
+> [!NOTE]
+> See full presentation slides at https://hackmd.io/@weiji14/foss4g2023oceania
+
 
 # Getting started