Feature work schedule (#1419)

* ifcopenshell.api modules Persons and Organisations account for IFC4 SCHEMA CHANGE

* New Feature to manpiulate Work Plans

src/ifcopenshell-python/ifcopenshell/api/sequence/edit_work_schedule.py

@@ -0,0 +1,13 @@
+class Usecase:
+    def __init__(self, file, **settings):
+        self.file = file
+        self.settings = {
+            "work_schedule": None,
+            "attributes": {}
+        }
+        for key, value in settings.items():
+            self.settings[key] = value
+
+    def execute(self):
+        for name, value in self.settings["attributes"].items():
+            setattr(self.settings["work_schedule"], name, value)