Updating "/back" and "/forward" to use new sig.
Updating "/back" and "/forward" to use new sig.

I changed PhantomJS signatures for "back" and "forward" to
"goBack" and "goForward"
stevenliuit/ghostdriver,asolntsev/ghostdriver,jesg/ghostdriver,Lochlan/ghostdriver,testingbot/ghostdriver,antoinereyt/ghostdriver,acarpe/ghostdriver,antoinereyt/ghostdriver,detro/ghostdriver,treejames/ghostdriver,Vitallium/ghostdriver,amikey/ghostdriver,testingbot/ghostdriver,jesg/ghostdriver,HelioGuilherme66/ghostdriver,HelioGuilherme66/ghostdriver,kuahyeow/ghostdriver,asolntsev/ghostdriver,detro/ghostdriver,kuahyeow/ghostdriver,51ttw/ghostdriver,xsyntrex/ghostdriver,jesg/ghostdriver,testingbot/ghostdriver,jesg/ghostdriver,Vitallium/ghostdriver,51ttw/ghostdriver,treejames/ghostdriver,xsyntrex/ghostdriver,yuanzhen/ghostdriver,HelioGuilherme66/ghostdriver,testingbot/ghostdriver,stevenliuit/ghostdriver,Lochlan/ghostdriver,detro/ghostdriver,acarpe/ghostdriver,amikey/ghostdriver,yuanzhen/ghostdriver