修改单元测试命名空间等

Changes to be committed:
	modified:   tests/framework/application/index/controller/indexTest.php
	modified:   tests/framework/thinkphp/library/think/cache/driver/apcTest.php
	new file:   tests/framework/thinkphp/library/think/cache/driver/cache_test_case.php
	modified:   tests/mock.php
	modified:   thinkphp/library/think/cache/driver/apc.php
	modified:   thinkphp/start.php

start.php

@@ -46,6 +46,6 @@ if (APP_HOOK && isset($mode['tags'])) {
 if ('sae' != APP_MODE && is_file(APP_PATH . 'build.php')) {
     Create::build(include APP_PATH . 'build.php');
 }
-
+Loader::addNamespace('tests',TEST_PATH);
 // 执行应用
 !IN_UNIT_TEST && App::run();