KAZOO-1802: fetch list of ignored hangup causes from config, and handle gen_listener casts
KAZOO-1802: add helper for setting monitor thresholds, add account summary listing
KAZOO-1802: fetch hangups to monitor from config, cleanup fetching meter stats
KAZOO-1802: handle gen_listener casts
KAZOO-1802: start monitoring server
KAZOO-1802: add folsom to list of ignored applications