Add interface methods for keeping pauses
Add interface method for playing a wait jingle
Simplify API for adding user audio to database

Don't expose the complex API for adding user audio to the database.
Define new simpler API methods for adding audio instead.
Extend interface test with special prompts
Drop legacy usage of column 'id' in database
Fix narration of integers
Fix incorrect handling of comments in csv files
Add spell function to narrator API
Add more prompts for narration of date and time
Remove link check for gst library

This check does not belong in the component.
Increase max values
Hide documentation for internal classes
Refactor check for required libraries