README: fix register signature
README: fix register signature

Zirpon/tchannel,vanloswang/tchannel,RyanTech/tchannel,i/tchannel,hustxiaoc/tchannel,davewhat/tchannel,savaki/tchannel,benfleis/tchannel,Zirpon/tchannel,chenwenbin928/tchannel,savaki/tchannel,sasa233/tchannel,hustxiaoc/tchannel,bunnyblue/tchannel,sasa233/tchannel,chenwenbin928/tchannel,bunnyblue/tchannel,benfleis/tchannel,i/tchannel,sasa233/tchannel,vanloswang/tchannel,vanloswang/tchannel,RyanTech/tchannel,bunnyblue/tchannel,benfleis/tchannel,Zirpon/tchannel,savaki/tchannel,chenwenbin928/tchannel,davewhat/tchannel,hustxiaoc/tchannel,i/tchannel,RyanTech/tchannel