Move job queue to redis

We'll use it as cache in the future.

/!\ You'll loose your old jobs (pending jobs too) so upgrade only when
you don't have pending job anymore.

server/helpers/custom-validators/jobs.ts

@@ -0,0 +1,14 @@
+import { JobState } from '../../../shared/models'
+import { exists } from './misc'
+
+const jobStates: JobState[] = [ 'active', 'complete', 'failed', 'inactive', 'delayed' ]
+
+function isValidJobState (value: JobState) {
+  return exists(value) && jobStates.indexOf(value) !== -1
+}
+
+// ---------------------------------------------------------------------------
+
+export {
+  isValidJobState
+}