nginx-rtmp 对一些客户端发送的请求并没有做出处理，比如说releaseStream 和FCPublish
log 跟踪：
2018/12/19 14:03:27 [debug] 8096#0: *1 AMF read (1) 02 '?'
2018/12/19 14:03:27 [debug] 8096#0: *1 AMF read (2) 00 0D '??'
2018/12/19 14:03:27 [debug] 8096#0: *1 AMF read (13) 72 65 6C 65 61 73 65 53 74 72 65 61 6D 'releaseStream'
2018/12/19 14:03:27 [debug] 8096#0: *1 AMF cmd 'releasestream' no handler
2018/12/19 14:03:27 [debug] 8096#0: *1 reusing formerly read data: 68
2018/12/19 14:03:27 [debug] 8096#0: *1 RTMP bheader fmt=1 csid=3
2018/12/19 14:03:27 [debug] 8096#0: *1 RTMP mheader fmt=1 amf_cmd (20) time=0+0 mlen=27 len=0 msid=0
2018/12/19 14:03:27 [debug] 8096#0: *1 RTMP recv amf_cmd (20) csid=3 timestamp=0 mlen=27 msid=0 nbufs=1
2018/12/19 14:03:27 [debug] 8096#0: *1 nhandlers: 1
2018/12/19 14:03:27 [debug] 8096#0: *1 calling handler 0
2018/12/19 14:03:27 [debug] 8096#0: *1 AMF read (1) 02 '?'
2018/12/19 14:03:27 [debug] 8096#0: *1 AMF read (2) 00 09 '??'
2018/12/19 14:03:27 [debug] 8096#0: *1 AMF read (9) 46 43 50 75 62 6C 69 73 68 'FCPublish'
2018/12/19 14:03:27 [debug] 8096#0: *1 AMF cmd 'fcpublish' no handler