Debug menu about evoli

[erlend-sh]

I assume we’d only use this for local play testing? Making imgui work for WASM deployment is out of scope for some time still, possibly always.

[khskarl]

Yes, it's really easy to gate this out when building for wasm.

We can gate out imgui code like this:

#[cfg(not(target_arch = "wasm32"))]
fn inspect(&mut self, entity: Entity, ui: &imgui::Ui<'_>) {
    ...imgui usage...
}

But I'm not sure if that's enough or we need to explicitly state somewhere that amethyst-inspector isn't a dependency when targeting wasm.

[khskarl]

Closing the issue as the inspector has been merged in #17 :).

[erlend-sh]

As this was temporarily disabled in #79 pending an update, I’m reopening this as a starter-friendly task.