restructure fs

example/program.nub

@@ -0,0 +1,19 @@
+import "core";
+
+func main() {
+    let i = 1;
+    while true {
+        let x = new Human
+        {
+            name = "test",
+            age = 34958743
+        };
+        
+        i = i + 1;
+    }
+}
+
+struct Human {
+    let name: String;
+    let age: int64;
+}