Added support for "current window switching" in the Session class.
Added support for "current window switching" in the Session class.

testingbot/ghostdriver,Lochlan/ghostdriver,HelioGuilherme66/ghostdriver,jesg/ghostdriver,stevenliuit/ghostdriver,Vitallium/ghostdriver,treejames/ghostdriver,acarpe/ghostdriver,stevenliuit/ghostdriver,HelioGuilherme66/ghostdriver,yuanzhen/ghostdriver,testingbot/ghostdriver,amikey/ghostdriver,Lochlan/ghostdriver,jesg/ghostdriver,51ttw/ghostdriver,HelioGuilherme66/ghostdriver,asolntsev/ghostdriver,kuahyeow/ghostdriver,asolntsev/ghostdriver,treejames/ghostdriver,detro/ghostdriver,jesg/ghostdriver,xsyntrex/ghostdriver,yuanzhen/ghostdriver,antoinereyt/ghostdriver,antoinereyt/ghostdriver,acarpe/ghostdriver,51ttw/ghostdriver,testingbot/ghostdriver,kuahyeow/ghostdriver,testingbot/ghostdriver,detro/ghostdriver,jesg/ghostdriver,detro/ghostdriver,amikey/ghostdriver,xsyntrex/ghostdriver,Vitallium/ghostdriver