Integrate Disqus in docwebsite and adapt it to eXo style
DOC-1679 Adapt style of disqus according to new version
DOC-1679 Move eXo footer below disqus
Merge branch 'stable/1.0.x' of github.com:exoplatform/docs-style into stable/1.0.x
PLFENG-1449 update navigation of 3.5 doc-website