Making a clean slate in preparation for the shelf implementation.
Created new project in preparation for the shelf implementation.
Added stub for ShelfManager.
Imported Baker classes as BakerView.
Renamed Shelf to BakerShelf.
Added test classes for Properties.
Added function initWithManifestString to Properties class.
Included sample book (A Study in Scarlet).
Added AQGridView lib to the project
Added ShelfViewController to the project
Added QuartzCore framework to the project (needed for AQGridView)
Changed the main window from UIWindow to InterceptorWindow
Create a navigation controller with an instance of the shelf controller as its root view controller and attached it to the main interceptor window
Updated the ShelfViewController as a subclass of AQGridViewController and
Implemented function localBooksList for ShelfManager class.
Merge branch 'shelf' of github.com:Simbul/baker into shelf
Downgraded ShelfManager to return an array of book paths instead of book properties
Added books array to shelf view controller and fill it with shelf manager local books list method
Did the basic setup of an AQGridViewController class to create a cell for each entry of the books array 
Handled shelf cells click: a new Baker View is allocated and pushed in the navigation stack
Added basic handling of the navigation bar behaviour in baker view controller (equal to status bar behaviour)