Changed "if" to "cond"
Part 2 - Chap 12: spawn examples
Part 2 - Chap 12: processes chain
Part 2 - Chap 12: two processes
Part 2 - Chap 12: spawn_link example
Part 2 - Chap 12: spawn_monitor example
Part 2 - Chap 12: spawn and sleep with spawn_link
Part 2 - Chap 12: spawn and sleep with spawn_link + exception raised
Part 2 - Chap 12: spawn and sleep with spawn_monitor

Only exit message was detected !