Create waardex alias for adkernel (#1542)

* Create waardex

Adding a new HB bidder description - WaardeX

* adding aliasCode header

dev-docs/bidders/waardex

@@ -0,0 +1,22 @@
+---
+layout: bidder
+title: WaardeX
+description: Prebid WaardeX Bidder Adaptor
+hide: true
+biddercode: waardex_ak
+aliasCode: adkernel
+media_types: display, video
+gdpr_supported: true
+---
+
+### Note:
+
+The WaardeX Bidding adaptor requires setup and approval before beginning. Please reach out to <welcome@waardex.com> for more details
+
+### Bid Params
+
+{: .table .table-bordered .table-striped }
+| Name     | Scope    | Description           | Example                   | Type     |
+|----------|----------|-----------------------|---------------------------|----------|
+| `host`   | required | Ad network's RTB host | `'cpm.webtradingspot.com'` | `string` |
+| `zoneId` | required | RTB zone id           | `'30164'`                 | `string` |