SDL client/server: add a RecvMessage function
SDL client/server: several general improvements, add a cleanup_server() function
SDL client/server: several improvements, code reorganization, add setup_server(), cleanup_client(), create_socketset() functions
SDL client/server: several general improvements, add a CreateSocketSet() function
SDL client/server: big reorganization of the code, several improvements
SDL client/server: add forgotten files
SDL client/server: several improvements, add add_client() and remove_client() functions
SDL client/server: add a README