feat: solver improvements + release v0.29.0 (#876)

* feat: solver improvements

* feat: add function to get/set whether gyroscopic forces are enabled on a rigid-body

* chore: switch to released versions of parry and wide instead of local patches

* fix cargo doc

* chore: typo fixes

* chore: clippy fix

* Release v0.29.0

* chore: more clippy fixes

src_testbed/lib.rs

@@ -9,8 +9,6 @@ pub use crate::plugin::TestbedPlugin;
 pub use crate::testbed::{Testbed, TestbedApp, TestbedGraphics, TestbedState};
 pub use bevy::prelude::{Color, KeyCode};
 
-#[cfg(all(feature = "dim2", feature = "other-backends"))]
-mod box2d_backend;
 #[cfg(feature = "dim2")]
 mod camera2d;
 #[cfg(feature = "dim3")]