adding PermitPool to etcd backend
adding PermitPool to etcd backend

chrishoffman/vault,naunga/vault,sepiroth887/vault,Caiyeon/vault,chris-west-travelex/vault,chris-west-travelex/vault,hashbrowncipher/vault,annanay25/vault,hashbrowncipher/vault,memory/vault,hashicorp/vault,hashbrowncipher/vault,kingland/vault,rnaveiras/vault,andrewstuart/vault,kingland/vault,rnaveiras/vault,mgk/vault,martin-ducar-gd/vault,grunzwei/vault,jgcallero/vault,mhurne/vault,andrewstuart/vault,doodles526/vault,geckoboard/vault,Aloomaio/vault,geckoboard/vault,MonsantoCo/vault,jmhardison/vault,careyblack/vault,quixoten/vault,jam-pot/vault,doubledutch/vault,wjam/vault,nickbourner/vault,geckoboard/vault,rnaveiras/vault,hashicorp/vault,mymercurialsky/vault,kingland/vault,danielsomerfield/vault,mgk/vault,kenbreeman/vault,jmhardison/vault,chris-west-travelex/vault,grunzwei/vault,michaelansel/vault,deverton/hashicorp-vault,quixoten/vault,hartsock/vault,peteryhwong/vault,cimarron-pistoncloud/vault,annanay25/vault,nickbourner/vault,careyblack/vault,rnaveiras/vault,kingland/vault,grunzwei/vault,sepiroth887/vault,mgk/vault,quixoten/vault,Aloomaio/vault,LolalyLuo/vault,hashicorp/vault,lemondrank/vault,careyblack/vault,doubledutch/vault,doodles526/vault,chris-west-travelex/vault,tallpauley/vault,mgk/vault,kenbreeman/vault,doubledutch/vault,jam-pot/vault,vicki-c/vault,deverton/hashicorp-vault,vicki-c/vault,kenbreeman/vault,careyblack/vault,Aloomaio/vault,annanay25/vault,kenbreeman/vault,andrewstuart/vault,nickbourner/vault,tallpauley/vault,skippy/vault,hartsock/vault,Banno/vault,skippy/vault,joelthompson/vault,hashicorp/vault,martin-ducar-gd/vault,MonsantoCo/vault,jmhardison/vault,geckoboard/vault,quixoten/vault,sepiroth887/vault,lemondrank/vault,hartsock/vault,hashicorp/vault,geckoboard/vault,annanay25/vault,joelthompson/vault,andrewstuart/vault,rnaveiras/vault,cimarron-pistoncloud/vault,peteryhwong/vault,nickbourner/vault,joelthompson/vault,jgcallero/vault,ryon/vault,mymercurialsky/vault,grunzwei/vault,chris-west-travelex/vault,lirao/vault,mhurne/vault,andrewstuart/vault,annanay25/vault,Aloomaio/vault,kingland/vault,jmhardison/vault,nickbourner/vault,danielsomerfield/vault,vicki-c/vault,ryon/vault,vicki-c/vault,doubledutch/vault,hashicorp/vault,hashbrowncipher/vault,hartsock/vault,vicki-c/vault,grunzwei/vault,doubledutch/vault,chrishoffman/vault,naunga/vault,hashbrowncipher/vault,Banno/vault,sepiroth887/vault,joelthompson/vault,sepiroth887/vault,LolalyLuo/vault,kenbreeman/vault,michaelansel/vault,jmhardison/vault,Caiyeon/vault,careyblack/vault,wjam/vault,hartsock/vault,memory/vault,lirao/vault