cmd/dockerd: add the link of "the documentation"
cmd/dockerd: add the link of "the documentation"

Signed-off-by: Akihiro Suda <10ddef0dea2a66ab193b07198faa879adcb213d8@hco.ntt.co.jp>

mahak/docker,Mokolea/docker,jthelin/docker,jthelin/docker,thaJeztah/docker,cpuguy83/docker,nawawi/docker,moul/docker,nalind/docker,moul/docker,trebonian/docker,djs55/docker,flavio/docker,Ramzec/docker,bearstech/moby,konstruktoid/docker-upstream,jimjag/docker,vdemeester/docker,flavio/docker,jimjag/docker,thaJeztah/docker,paralin/docker,jameszhan/docker,djs55/docker,Mokolea/docker,Mokolea/docker,Mokolea/docker,nalind/docker,trebonian/docker,jimjag/docker,konstruktoid/docker-upstream,nalind/docker,flavio/docker,moul/docker,gnailuy/docker,moby/moby,mahak/docker,nawawi/docker,trebonian/docker,moby/moby,vdemeester/docker,mahak/docker,yosifkit/docker,nawawi/docker,trebonian/docker,moby/moby,cpuguy83/docker,konstruktoid/docker-upstream,gnailuy/docker,yosifkit/docker,mahak/docker,moul/docker,nawawi/docker,Ramzec/docker,Ramzec/docker,jameszhan/docker,docker/docker,Ramzec/docker,vdemeester/docker,paralin/docker,bearstech/moby,paralin/docker,docker/docker,bearstech/moby,cpuguy83/docker,thaJeztah/docker,bearstech/moby,nalind/docker,jimjag/docker,gnailuy/docker,gnailuy/docker,flavio/docker,djs55/docker,cpuguy83/docker,moby/moby,yosifkit/docker,thaJeztah/docker,paralin/docker,docker/docker,jameszhan/docker,yosifkit/docker,konstruktoid/docker-upstream