PkvStore Resource fix

[Aultus-defora]

My attempt at fixing PkvStore not being a resource. Not sure if it is possible to add something smaller than bevy_ecs to dependencies. The error is PkvStore: bevy::prelude::Resource is not satisfied for Res<PkvStore>, ResMut<PkvStore>, ect.

[johanhelsing]

Thanks for the PR!

I wonder if it'd be possible to make bevy an optional dependency?

Something like:

#[derive(Debug)]
#[cfg_attr(feature = "bevy", derive(Resource))]
struct PkvStore {

Also, not sure what the practical difference is between importing bevy_ecs vs. importing bevy with default-features = false and then enable the features needed? I usually do the latter, but it would be good to know whether one approach has advantages over the other.

[Aultus-defora]

I am not sure what feature(s) is(are) enough to make #[derive(Resource)] work.

[Aultus-defora]

Now I use features to limit the Resource use, used cargo clippy to make linting good, also updated table — in 0.9 one has to at the very least create new struct with Resource to have PkvStore inside of a resource which is a hassle, this should solve that issue. P. S. I think adding bevy with no features as a dependency might be enough for it to work but I suspect bevy_ecs would be a smaller dependency than bevy

[johanhelsing]

Nice, this was exactly what I had in mind. Just a small error in the version table.

[Aultus-defora]

I merged the version table fix. Also confirmed that the #[cfg_attr(feature = "bevy", derive(Resource))] works.

[johanhelsing]

Aside from fixing the linting error. with cfg attributes, I find it cleaner to just fully qualify types