Bump stylo to 0.19.0, selectors to 0.39.0, to_shmem to 0.5.0 (servo#408)

Fixes: servo#407

Signed-off-by: Oriol Brufau <obrufau@igalia.com>

Bump stylo to 0.18.0 (servo#378)

d7e4d96 is the version servo's 0.3.0
release depends on, so we can just bump stylo on main.

Use prerelease syntax for 0.16.1 release

This is to avoid breaking any existing 0.16 users.
Servo can opt in to this prerelease.

Bump versions

- Bump stylo_* to 0.17.0
- Bump selectors to 0.38.0
- Bump to_shmem to 0.4.0

Signed-off-by: Oriol Brufau <obrufau@igalia.com>

Bump versions

- Bump stylo_* to 0.16.0
- Bump selectors to 0.37.0

Signed-off-by: Oriol Brufau <obrufau@igalia.com>

Bump stylo to 0.15 (servo#346)

cargo semver checks reports 4 breaking changes.
```
cargo semver-checks -p stylo --only-explicit-features --features servo
```

Bump selectors for readme update. (servo#335)

Bump versions

- Bump stylo_* to 0.13.0
- Bump selectors to 0.36.0

Signed-off-by: Oriol Brufau <obrufau@igalia.com>

Bump stylo_* to version 0.12.0

Signed-off-by: Oriol Brufau <obrufau@igalia.com>

Bump versions

- Bump stylo_* to 0.11.0
- Bump selectors to 0.35.0

Signed-off-by: Oriol Brufau <obrufau@igalia.com>