Don't default to rhino=true in the Rhino wrapper.
Don't default to rhino=true in the Rhino wrapper.

Defauling to the Rhino environment when Rhino is only used to run
JSHint is counter-intuitive and not aligned with other wrappers
such as Node.

Closes GH-507.

crivas/jshint,marian-r/jshint,freeyiyi1993/jshint,luisbrito/jshint,stevemao/jshint,scottsmeester/jshint,paul-wade/jshint,yadimon/jshint,mrjoelkemp/jshint,Endika/jshint,jagdeesh109/jshint,crivas/jshint,raix/jshint,gratex/jshint,meh-uk/jshint,shreyasgaonkar/jshint,gtanner/jshint,Jeremy017/jshint,louwers/jshint,gloryknight/jshint,davidjb/jshint,paul-wade/jshint,behind2/jshint,laurensortiz/jshint,ljharb/jshint,zynick/jshint,marian-r/jshint,jshint/jshint,mohsen1/jshint,gratex/jshint,AndriiGro/jshint,Jeremy017/jshint,thomas658/jshint,Joy603/jshint,beni55/jshint,gameclosure/jsiohint,lukeapage/jshint,darongE/jshint,niedzielski/jshint,elkingtonmcb/jshint,Khan/jshint,pansay/jshint,shreyasgaonkar/jshint,nicolo-ribaudo/jshint,lukeapage/jshint,mcanthony/jshint,BridgeAR/jshint,ghtest712/bearded-octo-dangerzone,beni55/jshint,yadimon/jshint,n8io/jshint,alivesay/jshint,llucbrell/jshint,nicolo-ribaudo/jshint,laurensortiz/jshint,cnbin/jshint,fashionsun/jshint,wzup/jshint,aisk/jshint,kidaa/jshint,ecomfe/edp-jshint,silverwind/jshint,doggy8088/jshint,n8io/jshint,BridgeAR/jshint,gtanner/jshint,kidaa/jshint,freeyiyi1993/jshint,fashionsun/jshint,jugglinmike/jshint,supriyantomaftuh/jshint,supriyantomaftuh/jshint,wisavalite/jshint,yyx990803/jshint,AndriiGro/jshint,jagdeesh109/jshint,stevemao/jshint,thomas658/jshint,mohsen1/jshint,llucbrell/jshint,behind2/jshint,max789/jshint,mcanthony/jshint,ljharb/jshint,paladox/jshint,niedzielski/jshint,davidjb/jshint,ThiagoGarciaAlves/jshint,aisk/jshint,wisavalite/jshint,louwers/jshint,lovemeblender/jshint,mrjoelkemp/jshint,jshint/jshint,kangax/jshint,rwaldron/jshint,paragag/AntiRedis,wzup/jshint,doggy8088/jshint,pansay/jshint,fairfieldt/jshint,goatslacker/jshint,scottsmeester/jshint,max789/jshint,alivesay/jshint,nitinlal/jshint,Joy603/jshint,jonnyreeves/jshint,jugglinmike/jshint,luisbrito/jshint,cnbin/jshint,SqrTT/dwhint,nitinlal/jshint,Endika/jshint,elkingtonmcb/jshint