Add removeObjectForKey method to IASKSettingsStore protocol.
Also implement this method in File and UserDefaults Settings store.
Updated README: IASK is now ARC-enabled
Improved subclassing of IASKAppSettingsViewController

by not removing all notification observers but just the ones we added
Merge pull request #225 from olicarbo/upstream

Add removeObjectForKey method to IASKSettingsStore protocol.
Ignore .xcuserdata
silence compiler warnings when implementing custom settings store (by @mman)
Fixed removal of NSUserDefaultsDidChangeNotification

close #234
Sample App: iOS 7 modifications

close #224
Support ShortTitles for Multi Value Elements (introduced in IOS 5.0)

thx @meizy
Fixed warnings and modernized build settings
Fixed issue with CUICatalog: Invalid asset name supplied: (null), or invalid scale factor: 2.000000
Merge branch 'master' into CDNCustomizations

* master:
  Fixed issue with CUICatalog: Invalid asset name supplied: (null), or invalid scale factor: 2.000000
  Fixed warnings and modernized build settings
  Support ShortTitles for Multi Value Elements (introduced in IOS 5.0)
  Sample App: iOS 7 modifications
  Fixed removal of NSUserDefaultsDidChangeNotification
  silence compiler warnings when implementing custom settings store (by @mman)
  Ignore .xcuserdata
  Improved subclassing of IASKAppSettingsViewController
  Updated README: IASK is now ARC-enabled
  Add removeObjectForKey method to IASKSettingsStore protocol. Also implement this method in File and UserDefaults Settings store.