Added an example to show how to use the \Predis\PubSubContext class.
Added an example to show how to use the \Predis\PubSubContext class.

quangnguyen90/predis,stokes3452/predis,johnhelmuth/predis,nrk/predis,oswaldderiemaecker/predis,CloudSide/predis,gencer/predis,protomouse/predis,gopalindians/predis,RedisLabs/predis,vend/predis,mrkeng/predis,SwelenFrance/predis,zhangyancoder/predis,RudyJessop/predis,moria/predis,lvbaosong/predis,dominics/predis,channelgrabber/predis,SecureCloud-biz/predis,WalterShe/predis,dzung2t/predis,nguyenthaihan/predis