Open graph meta performance

@Wikia/platform-team / @jacekjursza 

While going through data from profilers I found that ``egOgmcParserOutputApplyValues`` function (from 2011) takes 5-6% of response generation time (on each hit to the backend!). It was:

* making incorrect calls to ``ImageServing`` (passing a single article ID instead of an array)
* taking archived version of wiki wordmark, instead of using a const from ``ThemeSettings`` class

Then it turned out that the result of ``egOgmcParserOutputApplyValues`` function is override by SeoTweaks hook added in 2013.

5% of request time well spent :)

This change:

* simplifies ``egOgmcParserOutputApplyValues`` to render just the ``og:description`` meta tag (now it takes just 0,7-0,8% of total request time)
* adds profiling around the function
[fr] l'escription? :)