Release v1.10.0

• Added a new option maxrt(default 120 seconds) after which a checker task will be killed (ever had df hanging forever with a broken mount? :D). A checker can set self.maxrt to false/int-ish/proc(app, checker, checker_args). 0 or false will not enforce any time restriction.
  Note: In multi-thread mode checkers share the same connection and the net-ssh loop will block for the whole connection. This means a stalled df will most probably cause all other checkers for the same host/connection scheduled after it to fail as well (because they all wait for the df response and all hit the time limit)
• Added a new option conclosewait (default 10 seconds) to limit the amount of time WM will wait for connections to get closed (they sometimes just stall forever, especially if reaped by maxrt)
• Added new checker dev_pry that is mostly for development, if pry is installed and you are running threadless (-t0) you will get a pry console within the checker in which you can access app, checker and host e.g. host.exec("cat /proc/mdstat")
• Checkers will no longer attempt retries if WM is shutting down