* make cache_insert_data take effect in-service (fix #1521)
Signed-off-by: NYhz <yinghao.zou@zilliz.com>

* complete omitted config setter
Signed-off-by: NYhz <yinghao.zou@zilliz.com>

* cache_insert_data take effect for MemTable
Signed-off-by: NYhz <yinghao.zou@zilliz.com>

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

* rename config handler
Signed-off-by: NYhz <yinghao.zou@zilliz.com>