ncollide world update much slower in 0.22

After porting an application from 0.19 to 0.22 calling `CollisionWorld::update` after updating the positions of some objects is much slower than before, what used to take 0.3ms is now taking 1.2ms.

I've done a quick benchmark and what runs in 0.19 with nalgebra 0.18 in less than 3ms takes 12ms to run on 0.22 with nalgebra 0.20:

just uncomment the correct versions in the following cargo.toml and change the default features from old to new to test 0.22 instead of 0.19:

Cargo.toml
```toml
[package]
name = "ncollide-regression-bench"
version = "0.1.0"
edition = "2018"

# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

[dependencies]
# ncollide3d = "0.22"
# nalgebra = "0.20"

ncollide3d = "0.19"
nalgebra = "0.18"

[features]
old = []
new = []
default = ["old"]
```

lib.rs:
```rust
#![feature(test)]

extern crate test;
use test::Bencher;

#[cfg(feature="old")]
use ncollide3d::world::{CollisionWorld, CollisionGroups, GeometricQueryType};
#[cfg(feature="new")]
use ncollide3d::pipeline::{CollisionWorld, CollisionGroups, GeometricQueryType};
use ncollide3d::shape::{Cuboid, ShapeHandle};
use nalgebra::{Isometry3, Vector3, UnitQuaternion, Translation};

#[bench]
fn bench(b: &mut Bencher) {
let mut world = CollisionWorld::new(0.02);
let objects = (0..1000).map(|i| {
let pos = Translation::from(Vector3::new(i as f32, i as f32, i as f32));
let rot = UnitQuaternion::identity();
let position = Isometry3::from_parts(pos, rot);

let size = i as f32 * 0.1;
let cuboid = Cuboid::new(Vector3::new(size, size, size));
let shape = ShapeHandle::new(cuboid);

let groups = CollisionGroups::new()
.with_membership(&[0])
.with_whitelist(&[0]);

let query_type = GeometricQueryType::Contacts(0.0, 0.0);

let data = ();

#[cfg(feature="old")]
let handle = world.add(position, shape, groups, query_type, data).handle();

#[cfg(feature="new")]
let handle = world.add(position, shape, groups, query_type, data).0;

handle
}).collect::>();

let mut t = 0.;

b.iter(|| {
t += 1.;
for i in (0..1000).step_by(10){
let rot = UnitQuaternion::identity();
let x = i as f32 * t;
let pos = Translation::from(Vector3::new(x, x, x));
let position = Isometry3::from_parts(pos, rot);
let handle = objects[i];

#[cfg(feature="new")]
let _ = world.get_mut(handle).unwrap().set_position(position);

#[cfg(feature="old")]
let _ = world.set_position(handle, position);
}
world.update();
});
}
```