update/downgrade v1 to V2

build.rs

@@ -0,0 +1,9 @@
+extern crate winres;
+
+fn main() {
+  if cfg!(target_os = "windows") {
+    let mut res = winres::WindowsResource::new();
+    res.set_icon("icon.ico");
+    res.compile().unwrap();
+  }
+}