Bluej specific stuff
Init new project benzaiten.

Benzaiten is a very simple MP3-Management software.
The Class Song is already given.
Added already given class Song
Moved basic_concept.class.violet to doc/
Added empty class Benzaiten(administration, song library).
Added basic concept of Benzaiten.class
Changed - String[] getSongsByString --> - LinkedList<Song> getSongsByString(String)
Added first implementation based on doc/benzaiten_concept.class.violet
Added JUnit-Test
Added javadoc to Benzaiten.java