Support update metadata through MetadataManager

[osopardo1]

For implementing Convert To Qbeast (#102 ), we want to be able to add Qbeast Revision's metadata to the new log, without affecting the file entries.

The component in charge of communicating with the log (loading and committing new information) is the MetadataManager. At the current state of the MetadataManager, we can only call the method updateWithTransaction() which is implemented for updating the log with new committed files and table changes.

The idea is to write a new method to update ONLY with table changes. Something like:

  def updateMetadataWithTransaction(tableID: QTableID, schema: DataSchema, append: Boolean)(
      writer: => (TableChanges)): Unit = {}

[osopardo1]

Fixed on #152