When trying to search for hidden or disliked posts, it was impossible to search
by any aliases because of some hardcoded stuff. This commit removes the
hardcoded part altogether and fixes aliases support for these search terms.
* 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.
