Add Xcode project files.

To generate files, created a temporary project named UICKeychainStore.
In Xcode 4.6.3, created new project / empty application UICKeychainStore.
Didn't select git.
Chose unit tests.
Quit Xcode.
In Finder dragged files from temporary project to git repository UICKeychainStore forked from https://github.com/kishikawakatsumi/UICKeyChainStore.
Move code from UICKeyChainStoreTests.h to UICKeyChainStoreTests.m and delete UICKeyChainStoreTests.h.
Drag files from Finder to Xcode project navigator to make them visible within Xcode project.
Add Security.framework to targets.
In UICKeyChainStoreTests implement setUp, delete testExample, add testRemoveItemForKeyServiceAccessGroup.

On iPhone device, test passes.
Revise tests and add testSetStringForKey

In setUp to call removeAllItemsForService:accessGroup:
Rename testRemoveItemForKeyServiceAccessGroup to testRemoveAllItemsForServiceAccessGroup and call removeAllItemsForService:accessGroup:
Fix warning "Application Windows Are Expected To Have A Root View Controller At The End Of Application Launch".

Add MainStoryboard and MyViewController.
Improve testRemoveAllItemsForServiceAccessGroup.
Rename testRemoveAllItemsForServiceAccessGroup to testAddAndRemoveItem. Use instance "store" and instance methods.
Group tests into testClassMethodsSetAndRemoveItem and testInstanceMethodsSetAndRemoveItem.
Add comment about access group.
Add comment MIT License