Add config support to executor backend

Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>

daemon/dependency.go

@@ -0,0 +1,17 @@
+package daemon
+
+import (
+	"github.com/docker/swarmkit/agent/exec"
+)
+
+// SetContainerDependencyStore sets the dependency store backend for the container
+func (daemon *Daemon) SetContainerDependencyStore(name string, store exec.DependencyGetter) error {
+	c, err := daemon.GetContainer(name)
+	if err != nil {
+		return err
+	}
+
+	c.DependencyStore = store
+
+	return nil
+}