Much renaming and refreshing of RBE

rustbyexample/variable_bindings.d/scope.rs

@@ -0,0 +1,12 @@
+fn main() {
+    let long_lived_binding = 1;
+
+    {
+        let short_lived_binding = 2;
+        println!("inner short: {}", short_lived_binding);
+    }
+
+    // println!("outer short: {}", short_lived_binding);
+
+    println!("outer long: {}", long_lived_binding);
+}