Add vendoring to containerd master

Initial vendor list validated with empty $GOPATH
and only master checked out; followed by `make`
and verified that all binaries build properly.
Updates require github.com/LK4D4/vndr tool.

Signed-off-by: Phil Estes <estesp@linux.vnet.ibm.com>

vendor/google.golang.org/grpc/doc.go

@@ -0,0 +1,6 @@
+/*
+Package grpc implements an RPC system called gRPC.
+
+See www.grpc.io for more information about gRPC.
+*/
+package grpc // import "google.golang.org/grpc"