Add dependency on EventDispatcher
Factor duplicate lines
Add JobInterface::addSubscriber and JobInterface::addListener methods
Move memory limit detection to a subscriber
Add functional tests
Move duration limit detection to a subscriber
Move signal control to a subscriber
Move stop signal handling to a subscriber
Add job exception event
Add job exception event
Mock file locking to a subscriber
Require signal-handler, remove dev as minimum stability
Use signal handler instead of pcntl_signal calls