* Added few new operators that were left hardcoded
* Changed "Operator" to "Functor"
* Better hierarchy - less mess
* Serialized SQL queries should contain fewer braces
Instead of showing comments chronologically, group them into posts, then sort
the posts by last comment date. Reason: improved comment context delivery
makes discussion bumping possible (no matter how old it is) and discussion is
what comments are about.
Comment count is limited to 5 per post.
