[AC-3277] QA - Search needs to be drastically improved

I don't know what the search engine for QA is smoking, but it's not giving me any good search results... You should use a powerful search engine like [ElasticSearch](http://www.elasticsearch.org/) or [Solr](http://lucene.apache.org/solr/), if you already do, you're doing something wrong. The main reason for double-questions, angry users, and a generally bad community, is that you can't really find anything. If I try to search for a question I asked one week earlier, I often get the first page with 1 year old unanswered questions, sometimes even 2 years ago, when Titanium was only HTML... Search is so important, and you need to do it right. The search algorithm should take into consideration multiple factors, like how old the question is, upvotes/downvotes on questions/answers, the rank/experience of the user posting the question/answer, the view count, and more.