Implement local storage for todos example in Wasm

examples/todos/Cargo.toml

@@ -14,6 +14,10 @@ serde_json = "1.0"
 async-std = "1.0"
 directories = "2.0"
 
+[target.'cfg(target_arch = "wasm32")'.dependencies]
+web-sys = { version = "0.3", features = ["Window", "Storage"] }
+wasm-timer = "0.2"
+
 [package.metadata.deb]
 assets = [
     ["target/release/todos", "usr/bin/iced-todos", "755"],