sshuttle.md: fix whitespace issues.
sshuttle.md: fix whitespace issues.

dushmis/sshuttle,apenwarr/sshuttle,dxq-git/sshuttle,xtaran/sshuttle,GrimDerp/sshuttle,dushmis/sshuttle,shaunstanislaus/sshuttle,GrimDerp/sshuttle,xtaran/sshuttle,shaunstanislaus/sshuttle,xtaran/sshuttle,sshuttle/sshuttle,apenwarr/sshuttle,shaunstanislaus/sshuttle,dushmis/sshuttle,sshuttle/sshuttle,dxq-git/sshuttle,GrimDerp/sshuttle,dxq-git/sshuttle