docs: add update docs about the new CLI syntax
docs: add update docs about the new CLI syntax

postfix/gobgp,j-kato/gobgp,fujita/gobgp,h-naoto/gobgp,tamihiro/gobgp,osrg/gobgp,YujiOshima/gobgp,j-kato/gobgp,fujita/gobgp,osrg/gobgp,osrg/gobgp,a16/gobgp,a16/gobgp,j-kato/gobgp,postfix/gobgp,YujiOshima/gobgp,ramrunner/gobgp,a16/gobgp,h-naoto/gobgp,tamihiro/gobgp,h-naoto/gobgp,ishidawataru/gobgp,postfix/gobgp,a16/gobgp,a16/gobgp,ishidawataru/gobgp,osrg/gobgp,a16/gobgp,Dipsingh/gobgp,tamihiro/gobgp,Dipsingh/gobgp,ramrunner/gobgp,Dipsingh/gobgp,a16/gobgp,fujita/gobgp,YujiOshima/gobgp,ramrunner/gobgp,ishidawataru/gobgp,fujita/gobgp,tamihiro/gobgp