Client Login via device authorization flow (#309)

UI and CLI Clients are now able to use SSO login by default

we will check if the management has configured or supports SSO providers

daemon will handle fetching and waiting for an access token

Oauth package was moved to internal to avoid one extra package at this stage

Secrets were removed from OAuth

CLI clients have less and better output

2 new status were introduced, NeedsLogin and FailedLogin for better messaging

With NeedsLogin we no longer have endless login attempts

management/server/grpcserver.go

@@ -203,6 +203,9 @@ func (s *Server) registerPeer(peerKey wgtypes.Key, req *proto.LoginRequest) (*Pe
 		},
 	})
 	if err != nil {
+		if s, ok := status.FromError(err); ok && s.Code() == codes.FailedPrecondition {
+			return nil, err
+		}
 		return nil, status.Errorf(codes.NotFound, "provided setup key doesn't exists")
 	}