Fix the artv import.

Fix the artv import.
It couldn't handle the blank lines between sections and now it does.
Also added code to send dots during the room import to keep the user
informed that something is happening if we are importing a BIG room.
This has the added advantage of kicking the watchdog in sendcommand so
it doesn't time out unexpectedly.
Also added code to exit the artv early if we are shutting down.