Add json gem to dependency
Add json gem to dependency

inokappa/serverspec,mekf/serverspec,higanworks/serverspec,supertylerc/serverspec,serverspec/serverspec,elibus/serverspec,tacahilo/serverspec,uroesch/serverspec,ShawInnes/serverspec,mizzy/serverspec,sergueik/serverspec,aschmidt75/serverspec,ihassin/serverspec,RoboticCheese/serverspec,DarrellMozingo/serverspec,pfaffle/serverspec,minimum2scp/serverspec,Plus81/serverspec