Update Xcode project to be user and OSX version-agnostic

* All maxsdk references changed to $(maxsdk), instead of absolute path to jamie's Library location
* maxsdk reference must still be changed project-wide (unless your's is located at ~/Development/MaxSDK-6.1.4/c74support)
* All references to OS X 10.8 Deployment Target have been updated to "Latest OS X"