How to be TOC of SRS. (#3393)

1. If achieve 50+ commits, you will be a TOC.
2. CONTRIBUTING.md rules MUST be approved by Winlin and 3+ TOC.
3. Each PR MUST be approved by 2+ TOC or Developers.
4. The name of TOC will be listed at README.md forever.

Co-authored-by: john <hondaxiao@tencent.com>
Co-authored-by: LiPeng <lipeng19811218@gmail.com>
Co-authored-by: Haibo Chen <495810242@qq.com>
Co-authored-by: ChenGH <chengh_math@126.com>

CONTRIBUTING.md

@@ -5,3 +5,11 @@ Welome to contribute to SRS!
 1. Then follow the [guide](https://ossrs.io/lts/en-us/how-to-file-pr) or [贡献代码](https://ossrs.net/lts/zh-cn/how-to-file-pr) to file a PR.
 1. We will review your PR ASAP.
 
+If achieve [50 commits](https://github.com/ossrs/srs/graphs/contributors), you will be [TOC of SRS](https://github.com/ossrs/srs/blob/develop/trunk/AUTHORS.md#toc).
+
+* The update of this file MUST be approved by [Winlin](https://github.com/winlinvip) and 3+ [TOC](https://github.com/ossrs/srs/blob/develop/trunk/AUTHORS.md#toc).
+* Each [PullRequest](https://github.com/ossrs/srs/pulls) MUST be approved by 2+ [TOC](https://github.com/ossrs/srs/blob/develop/trunk/AUTHORS.md#toc) or [Developers](https://github.com/ossrs/srs/blob/develop/trunk/AUTHORS.md#developers).
+* The name of TOC will be listed at [README](https://github.com/ossrs/srs#authors) forever.
+
+All [contributors](https://github.com/ossrs/srs/blob/develop/trunk/AUTHORS.md#contributors) are listed in SRS authors.
+