Add sections for spatial and custom audio sources (#548)

Draft of the "Spatial Audio" and "Custom Audio Sources" sections.

[Rendered.](https://github.com/harudagondi/bevy-website/blob/audio-sections/content/news/2023-03-04-bevy-0.10/index.md#spatial-audio)

Co-authored-by: harudagondi <[email protected]>

Author: cart

content/news/2023-03-04-bevy-0.10/index.md

@@ -23,6 +23,47 @@ Since our last release a few months ago we've added a _ton_ of new features, bug
 
 Description here.
 
+## Spatial Audio
+
+<div class="release-feature-authors">authors: @mockersf, @DGriffin91, @harudagondi, @alice-i-cecile</div>
+
+The library Bevy uses for audio, [`rodio`], contains support for spatial audio. In this version, we now support spatial audio (with certain caveats, like no HRTF and no first class support for `Emitter` and `Listener` components).
+
+Interestingly, during the development of this specific feature, `@harudagondi` found a [bug][reverse-channels-bug] where the audio channels reverse when running the app in either debug or release mode. This turns out to be a `rodio` issue, and this also affects previous versions of Bevy. Thanks to `@dis-da-moe`, the bug has been [fixed upstream][rodio-pr]. See the linked PR for interesting details about audio programming quirks and performance issues.
+
+You can now have spatial audio in your game! Clone the `bevy` repository and invoke `cargo run --example spatial_audio_3d --release` in the command line for a showcase of 3D spatial audio in Bevy.
+
+[`rodio`]: https://crates.io/crates/rodio
+[reverse-channels-bug]: https://github.com/RustAudio/rodio/issues/444
+[rodio-pr]: https://github.com/RustAudio/rodio/pull/455
+
+## Custom Audio Sources
+
+<div class="release-feature-authors">authors: @dis-da-moe</div>
+
+Bevy supports custom audio sources through the [`Decodable`] trait, but the way to register to the bevy app is very boilerplatey and sparsely documented. In **Bevy 0.10**, a new extension trait for `App` is added and the documentation for [`Decodable`] has vastly improved.
+
+As such, instead of doing this:
+
+```rust
+struct MyCustomAudioSource { /* ... */ }
+
+app.add_asset::<MyCustomAudioSource>()
+    .init_resource::<Audio<MyCustomAudioSource>>()
+    .init_resource::<AudioOutput<MyCustomAudioSource>>()
+    .add_system(play_queued_audio_system::<MyCustomAudioSource>.in_base_set(CoreSet::PostUpdate))
+```
+
+You only have to do this:
+
+```rust
+app.add_audio_source::<MyCustomAudioSource>()
+```
+
+Much cleaner!
+
+[`Decodable`]: https://docs.rs/bevy_audio/latest/bevy_audio/trait.Decodable.html
+
 ## `Ref<T>` Queries
 
 <div class="release-feature-authors">authors: @Guvante, @JoJoJet</div>