feat: simple iterators and conditionals in rsx (#564)

* feat: simple iterators

* fix: into_iter

* feat: add support for unterminated conditionasl

* fix: add tempalte mapping for helpers

examples/simple_list.rs

@@ -8,12 +8,24 @@ fn app(cx: Scope) -> Element {
     cx.render(rsx!(
         // Use Map directly to lazily pull elements
         (0..10).map(|f| rsx! { "{f}" }),
+
         // Collect into an intermediate collection if necessary
         ["a", "b", "c"]
             .into_iter()
             .map(|f| rsx! { "{f}" })
             .collect::<Vec<_>>(),
+
         // Use optionals
         Some(rsx! { "Some" }),
+
+        div {
+            for name in 0..10 {
+                rsx! { "{name}" }
+            }
+
+            if true {
+                rsx!{ "hello world!" }
+            }
+        }
     ))
 }