Add an initial sample based on Apple's own tutorial

So, this is my first sample, creating the same sample as shown in Apple's tutorial of AppKit, doing the layout/event handling through code (I have a version that loads everything from the nib file, but we are missing action handling there).

I'm copying your default nib file for my sample, as I don't make use of it (i.e. setting any value for my objects). Lemme know ;)
maybe some stylized thing that conjures this
silhouette:
http://3.bp.blogspot.com/_kjphC6X6mrQ/TUsMV2HjP3I/AAAAAAAAAdo/LwpRbcjelwg/s1600/Pirouette.jpg

On Sun, Dec 7, 2014 at 5:11 PM, Larry Ewing <notifications@github.com>
wrote:

> In samples/TrackMixCode.app/Contents/Info.plist:
>
> > @@ -0,0 +1,24 @@
> > +<?xml version="1.0" encoding="UTF-8"?>
> > +<!DOCTYPE plist SYSTEM "file://localhost/System/Library/DTDs/PropertyList.dtd">
> > +<plist version="0.9">
> > +<dict>
> > +	<key>CFBundlePackageType</key>
> > +	<string>APPL</string>
> > +    	<key>CFBundleGetInfoString</key>
> > +	<string>TrackMixCode</string>
> > +	<key>CFBundleSignature</key>
> > +	<string>????</string>
> > +	<key>CFBundleExecutable</key>
> > +        <string>trackmixcode.js.exe</string>
> > +        <key>CFBundleIconFile</key>
> > +        <string>moonlight</string>
>
> So what kind of icon are you thinking?
>
> —
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