initial commit
Added some javadoc to the existing code.
Renamed project, added grid shape implementation.
Can shown alpha-shape on the guitar fretboart.

The fretboard is taken from image. The dots are drawn at runtime.
The solution works if the fret/string middles are hardcoded - they must
match to the image of the fretboard.

The positions for the absolute notes and for shapes in specific key are
shown correctly.
For detected with FFT note its positions are shown on the fretboard
Lessons refactored to the separate class. FFT + amplitued level used for Events.

Events are generated, only when the note is above some threshold of the amplitued.
The lessons are extracted from GuitarTrainerActivity to the separate class.
We have classes for: Note, GridShape, Degrees etc.

The views for basic controls are provided.
The main screen contains:
   * fret (no touches recognized currently)
   * shapes, degree boxes
   * notes view

The slide out menu was added, but the content of the menu itslef is
still to be defined.