Create "Foundation_Framework_Study" project, to learn and study how to programme with these foundation framework which Xcode Objective-C provides.

Add main.m,  Test.h  Test.m files.
Firstly study the NSNumber type of objects.

How to create the NSNumber type of objects, how to assign the values and how to invoke these objects.
Programming the NSString class of objects, and verify the usage of NSString class methods.
Design the test case to verify the NSString class of objects.
Finished the NSString objects test case.
插入一個強制類型轉換，消除warning.
1. Create a new module : Array_Object,   to study the usage of NSArray class.
    It contains under the sub-directory : Array_Object/

2. Perform the test case to test those functions about programming with NSArray class.
可變數組對象 NSMutableArray   的操作。
可變數組對象按照指定的方法進行排序。

對象 Student *stu1, *stu2, *stu3 裝入一個可變數組 NSMutableArray *students容器中， 按照@interface Student 中指定的排序方法 compareName:(id) element進行排序。

但測試結果顯示排序失敗，有可能是compareName方法實現的錯誤，留待以後來研究。
Create a new module "Dictionary_Object", to study how to program the NSDictionary & NSMutableDictionary class of objects.
編寫函數測試字典對象的創建與使用。