Prepare "excuse" messages for when location tracking is not activated

[gabrieljaegerde]

The admin might not always be able to activate location tracking (low battery etc.). Right now a lot of the interactivity of the bot is based around the location sharing. It would be nice to add more interactivity with the users sending the songs even if location tracking is not activated. Initially this could just be an excuse message randomly chosen from an array of prewritten possible messages (as it is done already in helpers.py with excuse_array). Later fancier interactions could be explored to still make the bot engaging without location tracking.