1.Implementation for rtp session module; 2.Separate signal server from main project

application/signal_server/main.cpp

@@ -0,0 +1,17 @@
+
+#include <iostream>
+
+#include "signal_server.h"
+
+int main(int argc, char* argv[]) {
+  SignalServer s;
+  std::string port = "";
+  if (argc > 1) {
+    port = argv[1];
+  } else {
+    port = "9090";
+  }
+  std::cout << "Port: " << port << std::endl;
+  s.run(std::stoi(port));
+  return 0;
+}