adding BEFORE_BIDDER_HTTP event (#3197)

* adding BEFORE_BIDDER_REQUEST event

* rename beforeBidderRequest to beforeRequestHttp

Signed-off-by: Elad Yosifon <elad@kueez.com>

* rename beforeRequestHttp to beforeBidderHttp

Signed-off-by: Elad Yosifon <elad@kueez.com>

dev-docs/publisher-api-reference/getEvents.md

@@ -26,6 +26,7 @@ The available events are:
 | auctionInit | The auction has started | Object containing auction details |
 | auctionEnd | The auction has ended | Object containing auction details |
 | beforeRequestBids | Bids are about to be requested from adapters (added in 3.x) | Array of adunits in the auction |
+| beforeBidderHttp | bidder network request is about be triggered | Array of Bid request objects |
 | bidRequested | A bid was requested from a specific bidder | Bid request object |
 | bidResponse | A bid response has arrived | Bid response object |
 | bidAdjustment | A bid was adjusted | Bid response object |