Filebrowser

- Integration of generic breadcrumb navigation in FileBrowser navigation
- Handling and styles of file favorites
Two important things:
* do not use absolute paths
* never use `/` or `\` in paths use `Paths.get(...)` instead or `File.separator`

```java
// replace "./foo/bar" with
Path p = Paths.get("foo", "bar")
// or
String s = "foo" + File.separator + "bar"
```