feat: add an unhygenic render macro (#556)

* feat: add an unhygenic render macro

* chore: use render instead of rsx!(cx,

packages/dioxus/tests/diffing.rs

@@ -9,7 +9,7 @@
 use dioxus::prelude::*;
 
 fn new_dom() -> VirtualDom {
-    VirtualDom::new(|cx| rsx!(cx, "hi"))
+    VirtualDom::new(|cx| render!("hi"))
 }
 
 use dioxus_core::DomEdit::*;