Use winit master temporarily

There are some web fixes upstream which are useful for the examples

Author: grovesNL

Cargo.toml

@@ -78,6 +78,7 @@ wasm-bindgen = { path = "../wasm-bindgen" }
 wasm-bindgen-futures = { path = "../wasm-bindgen/crates/futures" }
 web-sys = { path = "../wasm-bindgen/crates/web-sys" }
 js-sys = { path = "../wasm-bindgen/crates/js-sys" }
+winit = { git = "https://github.com/rust-windowing/winit", branch = "master" }
 
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
 env_logger = "0.7"