Add sounds when countdown reaches 0

[ManuelFeller]

Add some sounds for the last seconds and the finished countdown

[ManuelFeller]

This could be made more unique by having Sound-Themes insead of just single samples to choose from.

A theme could be made out of the following sounds:

• the one played one minute before 0 (max. 5 seconds length)
• the one played 30 seconds before 0 (max. 5 seconds length)
• the one played 10 seconds before 0 (max. 3 seconds length)
• the one played 5 seconds before 0 (max. 1.5 seconds length)
• the one played when 3, 2 or 1 seconds remain (max. 0.75 seconds length)
• then one played when time is up (max. 10 seconds length)