Add sections on redisCommandArgv and pipelining to README
Add sections on redisCommandArgv and pipelining to README

tattsun/hiredis,charsyam/hiredis,badboy/hiredis-win,h1048576/hiredis,rangan337/hiredis,hidebug/hiredis,tattsun/hiredis,lxfontes/hiredis,olgeni/hiredis,thomaslee/hiredis,texnician/hiredis-win32,nherment/arsenic,galdor/hiredis,owent-contrib/hiredis,yiliaofan/hiredis,arinal/hiredis,redis/hiredis,charsyam/hiredis,jinguoli/hiredis,chenlicong0821/hiredis,nokiddin/hiredis,koenvandesande/hiredis,owent-contrib/hiredis,picrin/redisSamples,hidebug/hiredis,Yhgenomics/hiredis,thomaslee/hiredis,Yhgenomics/hiredis,liulingfree/hiredis,thedrow/hiredis,xjzhou/hiredis,jqk6/hiredis,galdor/hiredis,Microsoft/hiredis,redis/hiredis,olgeni/hiredis,jinguoli/hiredis,liulingfree/hiredis,rangan337/hiredis,jinguoli/hiredis,xjzhou/hiredis,Microsoft/hiredis,chenlicong0821/hiredis,redis/hiredis