description:
1.add new interface description
2.modify taskpool cancel test
3.modify taskpool errorcode
4.modify utils errorcode
Signed-off-by: Nbuzhuyu <buzhuyu@huawei.com>

Signed-off-by: N葛亚芳 <geyafang@huawei.com>

description:
1.modify some test case
2.modify @concurrent description

issue:https://gitee.com/openharmony/docs/issues/I793KISigned-off-by: Nbuzhuyu <buzhuyu@huawei.com>

description:
1.修改taskpool.excute接口说明
2.修改taskpool.cancel接口说明
3.新增taskpool.cancel各情况示例
4.新增优先级示例

issue:https://gitee.com/openharmony/docs/issues/I6ZOIBSigned-off-by: Nbuzhuyu <buzhuyu@huawei.com>

1. add @concurrent
2. Stage model project and compilermode should be esmodule
Signed-off-by: Nwangzhaoyong <wangzhaoyong@huawei.com>
Change-Id: I146d55ac2ba5ce4b74f0eb27bdd49a2091cdd3c1

Signed-off-by: Nwangzhaoyong <wangzhaoyong@huawei.com>
Change-Id: I5d1209a395fb05991ff47cfa8b508e37b8e809d2

issue: https://gitee.com/openharmony/docs/issues/I6ALZNSigned-off-by: Nwangzhaoyong <wangzhaoyong@huawei.com>
Change-Id: I82f968b557c77acb85060a20b0318bb0a67b7a9d

Signed-off-by: Nwangzhaoyong <wangzhaoyong@huawei.com>
Change-Id: Ibbf8c6d08103b39a0b3a547b327bc4ca32d5e8a5

Signed-off-by: Nwangzhaoyong <wangzhaoyong@huawei.com>
Change-Id: I6542a2b3f50d676f6643023e9f3d7132bfdc26b4

issue: https://gitee.com/openharmony/docs/issues/I680I2Signed-off-by: Nwangzhaoyong <wangzhaoyong@huawei.com>
Change-Id: Id955a8cfe98f16db43be7078c35633cf11dee958