Migrate to hashbrown structures

src/dictionary.rs

@@ -18,7 +18,7 @@ use iced::widget::*;
 use iced::{Border, Color, Shadow, Task};
 use iced_core::Length::Fill;
 use rand::random_range;
-use std::collections::{HashMap, HashSet};
+use hashbrown::{HashMap, HashSet};
 use std::fs;
 use std::ops::Add;
 use std::path::PathBuf;