MP3 Player!

Some quick changes that were made:

• Allowing to add/remove discs when ever you want.
• Tweaked values with sliding the title
• Fixed that gui opens 2 times (you close one and another comes or if you want to change music while an disc is already playing)
• Fixed missing discs after inserting an while playing a disc
• Fixed duplicate discs merging into one
• Fixed playing sound status even after leave oder shutdown (/restart)