Comment 4 for bug 832507

The plan is:

1) Create a FIFO, open it persistently and use this as the console log destination
2) Write a handler that will write to a ring buffer on disk
3) Periodically read data out of the FIFO and give it to the handler
4) Also do step 3 before processing get_console_output
5) get_console_output now needs to read through the ring buffer implementation
6) Reopen the FIFO when Nova is restarted