Add encodeURIComponent to referer url (getTopWindowUrl) (prebid#2609)

* commit gamma adapter

* Fixed The Travis CI build failed

* fix interpretResponse return empty when server response empty

* removed mediaType

removed mediaType in bid 
and return vastXml property if video request

* fixed Travis CI build

* Travis CI build

* add gamma spec

* fixed Travis CI build

* fix spec

* fix spec

* Add files via upload

* Add files via upload

* fix spec

* fix Travis CI build

* move to module

* remove gaxDomain param and move to adapter

* remove check isBidRequestValid for gaxDomain

* remove gaxDomain param

* remove gaxDomain param

* remove gaxDomain param

* Delete gammaBidAdapter_spec.js

* add usersync endpoid

* add usersync

* add vastUrl

* add supportedMediaTypes to bidder spec

* add Test Parameters: For Video

* Add encodeURIComponent for referer url

modules/gammaBidAdapter.js

@@ -30,7 +30,7 @@ export const spec = {
     const gaxObjParams = find(bidRequests, hasParamInfo);
     return {
       method: 'GET',
-      url: '//' + ENDPOINT + '/adx/request?wid=' + gaxObjParams.params.siteId + '&zid=' + gaxObjParams.params.zoneId + '&hb=pbjs&bidid=' + gaxObjParams.bidId + '&urf=' + utils.getTopWindowUrl()
+      url: '//' + ENDPOINT + '/adx/request?wid=' + gaxObjParams.params.siteId + '&zid=' + gaxObjParams.params.zoneId + '&hb=pbjs&bidid=' + gaxObjParams.bidId + '&urf=' + encodeURIComponent(utils.getTopWindowUrl())
     };
   },