* set preload_table correctly (fix #1524)
Signed-off-by: NYhz <yinghao.zou@zilliz.com>

* update res name in http module (fix #1544)
Signed-off-by: NYhz <yinghao.zou@zilliz.com>

* add bool convertor function
Signed-off-by: NYhz <yinghao.zou@zilliz.com>

* fix test fail
Signed-off-by: NYhz <yinghao.zou@zilliz.com>

* optimize update config method & add boolean conversion comments
Signed-off-by: NYhz <yinghao.zou@zilliz.com>

* remove comments
Signed-off-by: NYhz <yinghao.zou@zilliz.com>