Add Docker support and configuration for SRS SIP

- Created a new README_cross.md file with Docker build instructions.
- Updated srs.conf to include logging configuration options.
- Added docker-compose.yml to define the SRS SIP service with necessary ports and volume mappings.
- Introduced config.yaml for general and GB28181-specific configurations.
- Added initial srs.conf with settings for RTMP, HTTP API, and WebRTC support.

conf/srs.conf

@@ -3,6 +3,11 @@ max_connections     1000;
 # For docker, please use docker logs to manage the logs of SRS.
 # See https://docs.docker.com/config/containers/logging/
 srs_log_tank        console;
+
+# srs_log_tank        file;
+# srs_log_file        /var/log/srs/srs.log;
+# ff_log_dir          /var/log/srs;
+
 daemon              off;
 disable_daemon_for_docker off;
 http_api {
@@ -57,4 +62,4 @@ vhost __defaultVhost__ {
         rtc_to_rtmp on;
         pli_for_rtmp 6.0;
     }
-}   
+}