update Dockerfile for Go 1.7 final
update Dockerfile for Go 1.7 final

rnaveiras/vault,lirao/vault,mgk/vault,jmhardison/vault,kingland/vault,martin-ducar-gd/vault,cimarron-pistoncloud/vault,hashicorp/vault,rnaveiras/vault,quixoten/vault,memory/vault,jam-pot/vault,michaelansel/vault,kingland/vault,doodles526/vault,peteryhwong/vault,cimarron-pistoncloud/vault,jmhardison/vault,jmhardison/vault,Aloomaio/vault,quixoten/vault,quixoten/vault,rnaveiras/vault,naunga/vault,jam-pot/vault,lemondrank/vault,hashicorp/vault,hartsock/vault,memory/vault,LolalyLuo/vault,danielsomerfield/vault,deverton/hashicorp-vault,hartsock/vault,joelthompson/vault,tallpauley/vault,jgcallero/vault,doodles526/vault,skippy/vault,LolalyLuo/vault,michaelansel/vault,wjam/vault,jgcallero/vault,martin-ducar-gd/vault,Banno/vault,mgk/vault,mgk/vault,mgk/vault,naunga/vault,kingland/vault,Caiyeon/vault,joelthompson/vault,skippy/vault,deverton/hashicorp-vault,hashicorp/vault,tallpauley/vault,Caiyeon/vault,Banno/vault,ryon/vault,wjam/vault,lemondrank/vault,peteryhwong/vault,jmhardison/vault,chrishoffman/vault,MonsantoCo/vault,hartsock/vault,rnaveiras/vault,hartsock/vault,hartsock/vault,Aloomaio/vault,MonsantoCo/vault,hashicorp/vault,hashicorp/vault,kingland/vault,danielsomerfield/vault,kingland/vault,Aloomaio/vault,chrishoffman/vault,jmhardison/vault,lirao/vault,joelthompson/vault,quixoten/vault,rnaveiras/vault,mymercurialsky/vault,hashicorp/vault,joelthompson/vault,Aloomaio/vault,ryon/vault,mymercurialsky/vault