SmartHub docs (#3131)

* adding SmartHub bidder docs

* removed pbjs version note

* using partner Name instead of host due to the changing way building endpoint URL in adapter
discussion in the prebid-server repo: prebid/prebid-server#1932 (comment)

Co-authored-by: bretg <bgorsline@gmail.com>

dev-docs/bidders/smarthub.md

@@ -0,0 +1,21 @@
+---
+layout: bidder
+title: SmartHub
+description: SmartHub Bidder Adapter
+biddercode: smarthub
+usp_supported: true
+schain_supported: true
+media_types: banner, video, native
+gdpr_supported: true
+pbjs: false
+pbs: true
+pbs_app_supported: true
+---
+
+### Prebid Server Bid Params
+{: .table .table-bordered .table-striped }
+| Name           | Scope    | Description                                              | Example    | Type      |
+|----------------|----------|----------------------------------------------------------|------------|-----------|
+| `partnerName` | required | Unique partner name | `'partnertest'`        | `string` |
+| `seat` | required | Seat value  | `'9Q20EdGxzgWdfPYShScl'`        | `string` |
+| `token` | required | Token  | `'eKmw6alpP3zWQhRCe3flOpz0wpuwRFjW'`        | `string` |