Not all files are observed for modifications

Say I have a mapping (CSVW) and a file with templates

```
/
└── mappings/
    ├── product.xrm
    └── templates.xrm
```

When I modify `product.xrm`, the generated `product.meta.json` is updated as expected

When I modify `templates.xrm`, `product.meta.json` is not updated even if it uses a template from the former 