Fix cargo test and a number of little cleanup bugs

examples/ssr.rs

@@ -6,7 +6,7 @@ use dioxus::prelude::*;
 
 fn main() {
     // We can render VirtualDoms
-    let mut vdom = VirtualDom::prebuilt(app);
+    let vdom = VirtualDom::prebuilt(app);
     println!("{}", dioxus_ssr::render(&vdom));
 
     // Or we can render rsx! calls themselves