[FEATURE] Support overrides to overwrite the lower-level Databricks Lakeview entities

[JCZuurmond]

From our docs:

Overrides are used to augment the metadata that is defined in the SQL files with the lower-level Databricks Lakeview entities.

A decision needs to be made on what level to inject the overrides.

Level	Unambiguous	Extensive	Easy of use
Top	Yes	Complete, change anything	Medium
Widget	No*	High, change widgets	High
Column	Yes	Low, change columns only	High

*not clear if it overwrites the dataset, "main" widget or filter widget