Add 'list' and 'print' builtins

src/evaluate.c

@@ -10,6 +10,10 @@
 #include <string.h>
 
 struct ucl_object *ucl_evaluate_list(struct ucl_state *state, struct ucl_object *list) {
+    if (list->cell.car == NULL) {
+        return list;
+    }
+
     // TODO: Recursively eval args
     struct ucl_object *evaluated_list = ucl_nil_create();