presses: Move press handling to Rust

This fixes some rendering things which would happen with multiple state-sharing buttons. It also removes some interfaces exposing rows, views, layouts, and buttons, bringing the code closer to removing them from the FFI entirely.

src/lib.rs

@@ -6,12 +6,13 @@ extern crate maplit;
 extern crate serde;
 extern crate xkbcommon;
 
+mod action;
 pub mod data;
 pub mod float_ord;
 pub mod imservice;
 mod keyboard;
 mod layout;
 mod resources;
-mod action;
+mod submission;
 mod util;
 mod xdg;