Chapter 45: Lifetimes and Assigning Renderable components

While going along with the tutorial, it was mentioned that you couldn't resolve the lifetime issues at the time. I am just dropping this off as a solution with lifetimes. My Renderer component differs slightly from the tutorial one, so I have adapted my code to it for this.

I believe the reason that the lifetimes are necessary, is because `EntityBuilder::with()` returns `Self`. This means that the passed `EntityBuilder` must live at least as long as `assign_render` is running, and since we build upon the passed builder, the one that we return must also live as long as the passed `EntityBuilder`, hence the connection between the three.

```Rust
fn assign_render<'a>(new_entity: EntityBuilder<'a>, render: &RawRender) -> EntityBuilder<'a> {
new_entity.with(Renderable {
glyph: render.glyph,
fg: render.fg,
bg: render.bg,
colors,
})
}
```