allow null values to pass through the JSON stringifier
allow null values to pass through the JSON stringifier

bac/juju-gui,mitechie/juju-gui,jrwren/juju-gui,jrwren/juju-gui,mitechie/juju-gui,bac/juju-gui,jrwren/juju-gui,jrwren/juju-gui,mitechie/juju-gui,mitechie/juju-gui,bac/juju-gui,bac/juju-gui