Some improvmenents in the Graph editor (design, messages).

Messagebox is shown before deleting an object from its window.
Some enhanced UI updates.

REST calls are async now BUT have to be tested (should produce problems with Unity UI thread...)

All scripts reviewed and updated to new API structures.
New assets for URP rendering.
TODO: update API method calls.

Update README.md

See merge request !12

Aktualisieren README.md

See merge request !11

Develop

See merge request !10

Fix: Statue scene.

See merge request !9

Fix: missing obj from statue.

See merge request !8

Statue model size was updated.

See merge request !7

# Conflicts:
#   UserSettings/Layouts/default-2021.dwlt

Add GraphView module & the World Storage inspector window into the main branch

See merge request !4

Merge into graph view

See merge request !5

WOrld Storage gizmos created for the use case.

# Conflicts:
#	Assets/ETSI.ARF/ARF World Storage API/Editor/Windows/TrackableWindow.cs
#	Assets/ETSI.ARF/ARF World Storage API/Editor/Windows/WorldAnchorWindow.cs
#	Assets/ETSI.ARF/ARF World Storage API/Editor/Windows/WorldLinkWindow.cs
#	Assets/ETSI.ARF/ARF World Storage API/Editor/Windows/WorldStorageWindow.cs
#	Assets/ETSI.ARF/ARF World Storage API/Materials.meta
#	UserSettings/Layouts/default-2021.dwlt
#	UserSettings/Search.settings

Create button now in the main window.
Different colors and icons for World Elements.

Draw gizmo for WorldLinks.
From/To link endpoints can now directly be selected in the scene.

Group concept as KeyValue.
Visual for trackables, anchors and link via prefabs.
Edit link now run well (TODO: drag/select elements?).
Code optimization in WorldLink.
TMP Pro for UI.