MacGui: Sparkle Updater initial implementation

MacGui: Sparkle Updater initial implementation
- Changed the call to hb_init to use "0" instead of the old check for updates at launch boolean value from the preferences
- Added Sparkle.framework to the xcode project
- Added "Check for updates..." menu item in the file menu
- Check for updates at launch in the preferences window now binds to SUCheckAtStartup in Shared User Defaults
- Macgui now checks for updates against our appcast at handbrake.fr/appcast.xml (this is specified in /macosx/HandBrake.plist as the value for the "SUFeedURL" which is added now.
- To check for update Sparkle compares the number in the "CFBundleVersion" (which is our build number) against the "sparkle:version="xxx"" in the enclosure tag in the appcast to trigger an update alert
- TO TEST: Change the CFBundleVersion in /macosx/HandBrake.plist to < 10101 (the dummy sparkle:version in the appcast right now) and build, upon launch you should get alerted of a new version available
- NOTE: The entire Sparkle.framework directory is added to the svn in this commit. Its 2.4 mb, though it looks like some things (particularly a ton of localized nibs) could be removed to slim it down quite a bit. As its the initial implementation and I know its tested I am committing the whole thing for this rev.

git-svn-id: svn://svn.handbrake.fr/HandBrake/trunk@1204 b64f7644-9d1e-0410-96f1-a4d463321fa5