docs(operators): add documentation for operator delay

src/operator-docs/utility/delay.ts

@@ -1,6 +1,73 @@
 import { OperatorDoc } from '../operator.model';
 
 export const delay: OperatorDoc = {
-  'name': 'delay',
-  'operatorType': 'utility'
+  name: 'delay',
+  operatorType: 'utility',
+  signature:
+    'public delay(delay: number | Date, scheduler: Scheduler): Observable',
+  parameters: [
+    {
+      name: 'delay',
+      type: 'number | Date',
+      attribute: '',
+      description: `The delay duration in milliseconds (a number) or a Date until which the
+      emission of the source items is delayed.`
+    },
+    {
+      name: 'scheduer',
+      type: 'Scheduler',
+      attribute: '',
+      description:
+        'The IScheduler to use for managing the timers that handle the time-shift for each item.'
+    }
+  ],
+  useInteractiveMarbles: true,
+  marbleUrl: 'http://reactivex.io/rxjs/img/delay.png',
+  shortDescription: {
+    description: `
+      Delays the emission of items from the source Observable by a given timeout or until a given Date.
+    `,
+    extras: []
+  },
+  walkthrough: {
+    description: `
+      <p>
+        If the delay argument is a Number, this operator time shifts the source Observable by that amount
+        of time expressed in milliseconds. The relative time intervale between the values are preserved.
+      </p>
+      <p>
+        If the delay argument is a Date, this operator time shifts the start of the Observable execution
+        until the given date occurs.
+      </p>
+    `
+  },
+  examples: [
+    {
+      name: 'Delay each click by one second',
+      code: `
+        const clicks = Rx.Observable.fromEvent(document, 'click').mapTo('click');;
+        const delayedClicks = clicks.delay(1000);
+        delayedClicks.subscribe(x => console.log(x));
+      `,
+      externalLink: {
+        platform: 'JSBin',
+        url: 'http://jsbin.com/howeziyoma/embed?js,console,output'
+      }
+    },
+    {
+      name: 'Delay all clicks until a future date happens',
+      code: `
+        const clicks = Rx.Observable.fromEvent(document, 'click');
+        const date = new Date('March 15, 2050 12:00:00');
+        const delayedClicks = clicks.delay(date);
+        delayedClicks.subscribe(x => console.log(x));
+      `,
+      externalLink: {
+        platform: 'JSBin',
+        url: 'http://jsbin.com/cozogifayu/embed?js,console,output'
+      }
+    }
+  ],
+  relatedOperators: ['debounceTime', 'delayWhen'],
+  additionalResources: []
 };