KAZOO-1104: remove completely useless callflow module
KAZOO-1104: updated specs, formatting, types, etc
KAZOO-1104: ensuring callflow modules only exit after calling a cf_exe method

No module should just terminate silently; should use the cf_exe functions
like continue, stop, etc.

Also cleaned up more specs and types, tickies.
KAZOO-1104: massive sed to replace wh_json:json_object with object
KAZOO-1104: no need to track self in state
KAZOO-1104: add/update types, spec
KAZOO-1104: start to resolve missing functionality
KAZOO-1104: call the appropriate sync function
KAZOO-1104: fix busted rebase, and update specs