[addProject] assets exported to wrong path

main project: khafile.js

```js
prj.addProject('libs/subproject');
```

sub projects khafile:

```
prj.addAssets('assets/**', {
    notInList: true,
    nameBaseDir: 'assets', destination: '{dir}/{name}', name: '{dir}/{name}',
});
```

Converted assets will be written to `./build/libs/subproject/assets/...` instead of `./build/debug-html5/`
