ADEN-1551 Disabling GPT, because Google serves 502s

Conflicts:
	extensions/wikia/AdEngine/js/AdConfig2.js
	extensions/wikia/AdEngine/js/AdConfig2Late.js
Merge pull request #5317 from Wikia/release-251-aden-1551-disable-gpt

ADEN-1551 Disabling GPT, because Google serves 502s