Workaround solution to help Yandex crawler index discource.

Yandex search engine doesn't index noscript tag content. See also
http://meta.discourse.org/t/noscript-tag-and-some-search-engines/8078
Fix recommendations from #1145
Merge pull request #1145 from abbat/yandex-workaround

Workaround solution to help Yandex crawler index discourse.