jsonstat: accept ints as strings or ints
json webserver: check for presence of command
json webserver: return masters as an Array
json webserver: add new 'zone' command

Replaces get-zone. Intended to replace zone-rest in the future, also
create/delete of zones should also go through this.
recursor json: put command into command var

Just like in the Auth.
WIP implement zone command in recursor json
WIP auth json: don't produce broken json with callback