Updated renet to bevy 0.15

[redjack96]

I needed bevy_renet for my bevy apps, so I have updated bevy to version 0.15 for all packages.

I also ported to bevy:0.15 the bevy examples and updated READMEs to specify the correct cargo features to run the examples.

The client for demo_bevy example requires a version update from smooth-bevy-cameras because glam version differs between the smooth-bevy-cameras:0.12 and bevy:0.15 crates; LookTransformPlugin and associated functions have been commented to be able to successfully compile this example.

The bevy_renet crate has been tested on one of my app and works correctly with bevy:0.15.
The "simple" example works correctly with server and client.
The demo_bevy example's server runs, but the client needs smooth-bevy-cameras:0.13

All tests pass with cargo test.

The branch is ready to merge, but feel free to wait until smooth-bevy-cameras:0.13 is available

[lucaspoffo]

Thanks! Will probably remove the smooth-bevy-cameras from the demo, a simple smooth camera follow system should do it.