1. delete bt task from cloud only for full download. That is, if you have a bt task, and the bt task has 100 files, if you choose to download one of those files, we won't delete the whole task after this download is done, as you may want to download others later. 2. fix a missing delete_task in one code branch.
1. delete bt task from cloud only for full download. That is, if you have a bt task, and the bt task has 100 files, if you choose to download one of those files, we won't delete the whole task after this download is done, as you may want to download others later.
2. fix a missing delete_task in one code branch.

davies/xunlei-lixian,sndnvaps/xunlei-lixian,wogong/xunlei-lixian,sdgdsffdsfff/xunlei-lixian,wangjun/xunlei-lixian,myself659/xunlei-lixian,iambus/xunlei-lixian,liujianpc/xunlei-lixian,windygu/xunlei-lixian,xieyanhao/xunlei-lixian,ccagg/xunlei,GeassDB/xunlei-lixian