Adds base files

Project package structure is created.

ID3 v2.4.0 specification is added. Also a test MP3 file is added.
This file contains 10 seconds of a 1 kHz beep tone done in Audacity
(be careful when listening it, even if I made it quiet). What's
relevant inside this file is the ID3 tags:

* Artist: TestArtist
* Title: TestTrack
* Album: TestAlbum
* Comment: TestComment
* Track ID: 1
* Year: 2013
* Genre: Other