Use a view for Lubis Viewer

The purpose of this PR is #457 

In this PR:
- A custom view has been created for Lubis fullscreen viewer.
- Related test have been added
- An example has been added in the dev page #438 
- Extended html popups have cleaned up
- Agnostic urls are used
- One redundant template has been removed (for data outside Swisstopo, one only need to check whether contact_web attribute exists or not)