Add ability to create Icons from embedded resources on Windows (#1410)

* Add IconExtWindows trait

* Move changelog entries to unreleased category

Co-authored-by: Osspial <osspial@gmail.com>

src/platform_impl/web/mod.rs

@@ -44,3 +44,5 @@ pub use self::window::{
     Id as WindowId, PlatformSpecificBuilderAttributes as PlatformSpecificWindowBuilderAttributes,
     Window,
 };
+
+pub(crate) use crate::icon::NoIcon as PlatformIcon;