Only unwrapping webhook payloads if necessary

packages/rocketchat-integrations/server/api/api.coffee

@@ -50,6 +50,12 @@ Api = new Restivus
 	apiPath: 'hooks/'
 	auth:
 		user: ->
+			payloadKeys = Object.keys @bodyParams
+			payloadIsWrapped = @bodyParams?.payload? and payloadKeys.length == 1
+
+			if payloadIsWrapped and @request.headers['content-type'] is 'application/x-www-form-urlencoded'
+				@bodyParams = @bodyParams.payload
+
 			@integration = RocketChat.models.Integrations.findOne
 				_id: @request.params.integrationId
 				token: decodeURIComponent @request.params.token