Add removeObjectForKey method to IASKSettingsStore protocol.
Also implement this method in File and UserDefaults Settings store.
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' of https://github.com/futuretap/InAppSettingsKit

Conflicts:
	.gitignore
	InAppSettingsKit/Models/IASKSpecifier.m