Return closures from conditions

[Shatur]

In Bevy all conditions done this way. See the the example. Let's make them consistent with the rest of the engine.

[Shatur]

Added two more condition that should replace #95. Similar to https://docs.rs/bevy/latest/bevy/input/struct.Input.html#method.just_pressed.

[lucaspoffo]

Added two more condition that should replace #95. Similar to https://docs.rs/bevy/latest/bevy/input/struct.Input.html#method.just_pressed.

Yeah, I prefer doing like this instead of events 👍

[lucaspoffo]

Thanks!