Add clippy, fix up warnings

enkou-shaders/src/lib.rs

@@ -1,6 +1,7 @@
 //! # Enkou
 #![no_std]
-#![warn(missing_docs)]
+#![deny(missing_docs)]
+#![allow(clippy::needless_range_loop)] // SPIR-V backend has issues with iteration over items
 
 pub mod camera;
 pub mod chaos_game;