學習研究C++編程  《C++ Primer》 經典著作

在Apple Mac OS X的Xcode的開發環境下學習研究C++編程

創建第一個項目：Study_Class

Initial commit.
Append a new ignored type : *.xcuserstate

This type is automatically changed as the Xcode environment.
Delete the untracking file type *.xcuserstate

It was originally added into git tracking list, but it is intermediate and arbitrary.

Append this type into .gitignore list.
Study How to implement the constructor overloading, and verify how multi-constructors work?
1. 從const成員函數返回 *this

2. 基於 const 的成員函數重載

3. 可變數據成員
Merge branch 'master' of github.com:xu-zan/CPP_Primer

Conflicts:
	.gitignore
Add and edit the Project Makefile.
將Makefile文件添加進Study_Class.xcodeproj 項目中去。