Updated mapLayers collection (2SP)

[bariela]

Functional requirements

'mapLayers' collection has right now mixed displaying configuration with data about displayed data. In new data structure, this informations will be split, this collection will be handling only configurational part.

Technical requirements

Move metadata about geo data and attributes in their collection in metadata objects, if not done before
when fetching staticLayers, get this metadata and include them in returned items

Dependencies

69 #73

Definition of done

• [ ] Metadata about attributes and geoData are not stored in 'mapLayers' collection, only in their respective collections, but still are fetched for frontend to be in info detail
• [ ] documentation is updated
• [ ] tutorials are up to date with changes