repositorySpecsManaged flag in build plan configuration response

This response of /rest/api/1.0/deploy/project/{deploymentProjectId} contains a flag to let you know if that project is managed by repository stored specs.

It would be helpful if /rest/api/1.0/plan/{projectKey}-{buildKey}, or similar, contained the same flag.

{
   ...
   "repositorySpecsManaged": true,
   ...
}