Variables for import's and export's path

```dart
path "package:MyProject" as root;
path "$root/long/long/path/models" as models;
path "$root/long/long/path/views" as views;

import "$models/my_model.dart";
import "$views/my_view.dart";

import "$views/$old_name_works_fine/other_view.dart";

export "$models/my_model.dart";
export "$views/my_view.dart";
```