Add --dirty-ping method to ping the pool in case it does not sent any job after timeout
Add --timeout to specify the pool timeout
Reset timeout when a ACCEPT/REJECT share is sent from origin pool
Simplify sharestats module (no more dirty job storage)
Add accept/reject parameter to sharestats, statistics working now
Store difficulty in Job's class, so if new job is given but clean_jobs=False sharenotify can still know which was the job difficulty
Change some sharestats references to sharenotify (makes more sense)
Add threading for sharenotify, so the snippet is not blocking