Automate styleguide routes/navigation

[patric-eberle]

The navigation of the styleguide could be automated and build based on the folder structure and maybe additional exports for title or other meta information form the SFC.

• Creating a vue file in the styleguide route folder adds a new entry to the styleguide navigation.
• The url name is created from folder and file name.
• Additional information (e.g. a detailed title or query attributes) can be defined by an additional export from the vue component file.