Enhancement

• Added idle_worker_num and task_idle_worker_num to Server::stats (#2687) (@matyhtf)
• PHP7.4 Compatibility (5bf6491) (@twose) (#2707) (@remicollet)
• Clear reactor when error occured (61536e7) (@twose)

Fixed

• Fixed Socket->sendto (7bd8492) (@twose)
• Fixed WaitGroup->wait timeout type (acf20c3) (@twose)
• Fixed #2710 (#2710) (@twose)
• Fixed event num of signal in OSX (cf32c35) (@matyhtf)