HLS: Support HLS-PLUS(HLS)+ Edge Cluster

[winlinvip]

Read ossrs/srs#466

For origin: Publish stream to server, remux the stream to HLS in memory.
For edge: Play the HLS, fetch from upstream, remux the stream to HLS in memory.

The wiki: Not ready.

[winlinvip]

For RTMP: #37
For FLV: #36
For HLS: #35

[winlinvip]

8eb08d7

HLS+可以使用HTTP 302，来标识HLS客户端播放器，形成伪连接。

[winlinvip]

#58 (comment)

[winlinvip]

#58 (comment)

[rukesun]

For origin: Publish stream to server, remux the stream to HLS in memory.
For edge: Play the HLS, fetch from upstream, remux the stream to HLS in memory.

@winlinvip 请问SRS哪个版本支持HLS/HLS+ Edge Cluster功能？如果已支持，请问是否有相关的配置文档说明？

[rukesun]

已在《SRS产品规划》中找到答案，谢谢！
https://github.com/ossrs/srs/wiki/v1_CN_Product
SRS release 3.0，研发阶段。主要的目标是：
[plan]支持HLS边缘服务器。参考：#466.
[plan]支持HLS低延迟模式。参考：#468.

[winlinvip]

可能会推迟到SRS4 😿
Maybe postpone to SRS4.