add tests for cross model forward references, add docs for processing forwardrefs, wip on refactoring queries into separate pages based on functionality

docs/queries/update.md

@@ -0,0 +1,71 @@
+# Update
+
+*  `update(each: bool = False, **kwargs) -> int`
+*  `update_or_create(**kwargs) -> Model`
+*  `bulk_update(objects: List[Model], columns: List[str] = None) -> None`
+*  `Model.update() method`
+*  `Model.upsert() method`
+*  `Model.save_related() method`
+
+## update
+
+`update(each: bool = False, **kwargs) -> int`
+
+QuerySet level update is used to update multiple records with the same value at once.
+
+You either have to filter the QuerySet first or provide a `each=True` flag to update
+whole table.
+
+If you do not provide this flag or a filter a `QueryDefinitionError` will be raised.
+
+Return number of rows updated.
+
+```Python hl_lines="26-28"
+--8<-- "../docs_src/queries/docs002.py"
+```
+
+!!!warning Queryset needs to be filtered before updating to prevent accidental
+overwrite.
+
+    To update whole database table `each=True` needs to be provided as a safety switch
+
+## update_or_create
+
+`update_or_create(**kwargs) -> Model`
+
+Updates the model, or in case there is no match in database creates a new one.
+
+```Python hl_lines="26-32"
+--8<-- "../docs_src/queries/docs003.py"
+```
+
+!!!note Note that if you want to create a new object you either have to pass pk column
+value or pk column has to be set as autoincrement
+
+## bulk_update
+
+`bulk_update(objects: List["Model"], columns: List[str] = None) -> None`
+
+Allows to update multiple instance at once.
+
+All `Models` passed need to have primary key column populated.
+
+You can also select which fields to update by passing `columns` list as a list of string
+names.
+
+```python hl_lines="8"
+# continuing the example from bulk_create
+# update objects
+for todo in todoes:
+    todo.completed = False
+
+# perform update of all objects at once
+# objects need to have pk column set, otherwise exception is raised
+await ToDo.objects.bulk_update(todoes)
+
+completed = await ToDo.objects.filter(completed=False).all()
+assert len(completed) == 3
+```
+
+## Model method
+