feat:修改composer

@@ -4,7 +4,8 @@
   "require": {},
   "autoload": {
     "psr-4": {
-      "jiaoyin\\php-common\\": "/"
+      "Jiaoyin\\Db\\": "/db",
+      "Jiaoyin\\Exchange\\": "/exchange"
     }
   }
 }

 <?php
-namespace Jiaoyin\DbManage;
+namespace Jiaoyin\Db;
 
 class MysqlCli{
     public function start(){

 <?php
 
-namespace Jiaoyin\Test;
+namespace Jiaoyin\Exchange;
 
 class Test {
     public function sayHello() {