table_metadata should indicate whether table dictionary was parsed from sources or derived

[fedorov]

By "derived" I refer to the situation where column_metadata values column was populated by examining the actual values encountered for the specific column names.

[G-White-ISB]

That will be in for v12.

[G-White-ISB]

The field values_source in the column_metadata table records whether the values were determined by inspection or provided by a data dictionary