Replace deprecated methods, and move to Xcode 5.
Add notification center support

Similar to and partially based on [pull request 16](https://github.com/salomvary/soundcleod/pull/16).

Although @reaperhulk prefers the notifications to be optional, I think
its ok to have them enabled by default. First, that's what iTunes does
(Apple is always right). Second, it's simpler to implement. Third, it
can still be disabled as all other notifications in system preferences.
Properly handle sets
Merge pull request #39 from yep/master

Add notification center support
fix #34 Closing window stops music
ignore Xcode 5 .xccheckout files
fix webview not shown in production build
v0.11
configurable base url for debugging

usage:
defaults write sc.soundcleod BaseUrl "http://wherever/you/want/to/start"

go back to normal:
defaults delete sc.soundcleod BaseUrl
added Sparkle to the soup
configured for Sparkle
release 0.12
v0.12
added basic makefile
Merge branch 'master' of https://github.com/salomvary/soundcleod