Remove everything that was marked #[deprecated] (#8105)

Simplify. Streamline. Spring cleaning.

crates/epaint/src/lib.rs

@@ -71,15 +71,9 @@ pub use self::{
     viewport::ViewportInPixels,
 };
 
-#[deprecated = "Renamed to CornerRadius"]
-pub type Rounding = CornerRadius;
-
 pub use ecolor::{Color32, Hsva, HsvaGamma, Rgba};
 pub use emath::{Pos2, Rect, Vec2, pos2, vec2};
 
-#[deprecated = "Use the ahash crate directly."]
-pub use ahash;
-
 pub use ecolor;
 pub use emath;