Implemented --fork
Implemented support for --restore and --status for --fork'ed sessions
Send SIGUSR2 to child processes on a keypress, and have them print status upon
receipt of this signal
Prefix the status line with node number when running a --fork'ed session
Print the status line to stderr all at once, not piece by piece
Unlock the .rec file before closing it when we intend to re-open the file for
writing and lock it again.  This appears to help avoid a race condition on
Linux where a subsequent rec_lock() would fail (flock() failing with
EWOULDBLOCK) if too little time elapses yet the process happens to be bounced
to a different CPU.
Prefix log file lines with node number when running a --fork'ed session
Don't try to signal the (non-existent) child processes when we're not --fork'ed
1.7.9.12:
The --fork=N option has been added
Merge branch 'master' into bleeding-jumbo

* master:
  1.7.9.12: The --fork=N option has been added
  Don't try to signal the (non-existent) child processes when we're not --fork'ed
  Prefix log file lines with node number when running a --fork'ed session
  Unlock the .rec file before closing it when we intend to re-open the file for writing and lock it again.  This appears to help avoid a race condition on Linux where a subsequent rec_lock() would fail (flock() failing with EWOULDBLOCK) if too little time elapses yet the process happens to be bounced to a different CPU.
  Print the status line to stderr all at once, not piece by piece
  Prefix the status line with node number when running a --fork'ed session
  Send SIGUSR2 to child processes on a keypress, and have them print status upon receipt of this signal
  Implemented support for --restore and --status for --fork'ed sessions
  Implemented --fork

Conflicts:
	src/logger.c
	src/options.c
	src/options.h
	src/params.h
	src/recovery.c
	src/signals.c
	src/signals.h
	src/status.c