Spatial Elements Utilities and QOL (#2008)

* Tool to add storey to specific building

* Operator to add new storey to building

* Add new storey to building button in aggregates panel

* Minor fix

* add method to data class to retrieve ifc class name

* Extract aggregate creation logic

* Prevent aggregating non-ifc elements + display popup info

* Add tooltips + rename operators

* Rename function to get relating object

* Rename relating object data variable to be able to have access to related objects

* Add utilities to get related objects

* Add utility function to get related objects from element

* display related object in Aggregates panel in object properties

* Revert "Rename function to get relating object"

This reverts commit 5248627a41.

* Update method names

* Add Operator to select parts of an element

* Ditch box layout and only display number of parts

* Add operator to select aggregate of an element

* Display operator to select aggregate of element

* Move logic to aggregate module

* Add utility methods to Blender tool

* Add buttons to create Ifcsite and IfcBuilding from object panel

src/ifcopenshell-python/ifcopenshell/util/element.py

@@ -183,6 +183,11 @@ def get_aggregate(element):
         return element.Decomposes[0].RelatingObject
 
 
+def get_parts(element):
+    if hasattr(element, "IsDecomposedBy") and element.IsDecomposedBy:
+        return element.IsDecomposedBy[0].RelatedObjects
+
+
 def replace_attribute(element, old, new):
     for i, attribute in enumerate(element):
         if has_element_reference(attribute, old):