TC-4653 : Add access to iOS App Setting URL

Add access to the iOS8 UIApplicationOpenSettingsURLString. This allows the developer to launch directly into the iOS8 App Settings Screen using Ti.Platform.canOpenURL.

For example:

~~~
var settingsURL = Ti.App.iOS.applicationOpenSettingsURL;
if(settingsURL!=undefined){
	if(Ti.Platform.canOpenURL(settingsURL)){
		Ti.Platform.openURL(settingsURL);
	}else{
 	alert('cannot open URL');
 }
}

~~~
Description looks good. But line 259 to line 263, remove the 'tabs', the doc generator will fail when 'tabs' are encountered. In github, you can 'view whole file' and you will see what i mean.