Updates the line once per second rather than once per frame, saving quite a bit of CPU. Also completely stops the script while paused. That aside, fixes the swapped checks for video and audio-only files and adds bitrate printing.
Also mention that this code does not reflect the status line of current mpv.
Looks like TOOLS/lua/ is now established as dumping ground for random Lua scripts, so DOCS/lua_examples/ is not needed anymore.