remove redundant folder structure
Convert to ARC. Modernize array and NSNumber notation. Modernize deprecated calls.
Modernize AppDelegate and InvoiceController. Clean up nib file.
Workaround 10.9 bug with Invoice export and PDF rendering. Layer-backed views are drawn flipped at PDF (0,0), and many of our text views are apparently layer-backed scroll views. Also simplify debug assertion defines.
remove xcode user files from repository
Add gitignore file.