use contants for defaults, use a common doctype

add tests, update readme

src/job.js

@@ -2,7 +2,7 @@ import events from 'events';
 import isPlainObject from 'lodash.isplainobject';
 import Puid from 'puid';
 import logger from './helpers/logger';
-import { jobStatuses } from './helpers/constants';
+import contstants from './helpers/constants';
 import createIndex from './helpers/create_index';
 
 const debug = logger('esqueue:job');
@@ -23,10 +23,11 @@ export default class Job extends events.EventEmitter {
     this.timeout = options.timeout || 10000;
     this.maxAttempts = options.max_attempts || 3;
     this.priority = Math.max(Math.min(options.priority || 10, 20), -20);
+    this.doctype = options.doctype || contstants.DEFAULT_SETTING_DOCTYPE;
 
     this.debug = (...msg) => debug(...msg, `id: ${this.id}`);
 
-    this.ready = createIndex(client, index)
+    this.ready = createIndex(client, index, this.doctype)
     .then(() => {
       return this.client.index({
         index: this.index,
@@ -40,7 +41,7 @@ export default class Job extends events.EventEmitter {
           created_at: new Date(),
           attempts: 0,
           max_attempts: this.maxAttempts,
-          status: jobStatuses.JOB_STATUS_PENDING,
+          status: contstants.JOB_STATUS_PENDING,
         }
       })
       .then((doc) => {