TMA- Track Mix App Tutorial Initial Commit

Tutorial from
https://developer.apple.com/library/mac/referencelibrary/GettingStarted/
RoadMapOSX/books/RM_YourFirstApp_Mac/Articles/Introduction.html

This app has a set of controls that you can use to set the volume of an
audio track.
Add .gitignore and remove unnecessary tracked file
TMA- Add UI elements and connect them.

- Modified NIB to add a text field, a vertical slider, and a push
button into the window.
- Made appropriate connections between the UI elements and code by:
    * creating actions so UI elements can send messages to the App
Delegate
    * creating outlet connections from the app delegate to the text
field and slider.
- Added log statements to the action methods for testing the
connections made.
Bringing README.