Make thread highlighting override hiding

[brsk93]

Could it be possible to have highlighted threads override the normal thread hiding according to filters? For example, if I have a determined word filtered, but want to highlight a thread in particular that happens to contain that same word. Right now it doesn't seem to work. It only partially works if I watch a hidden thread. That puts the outline on it, even brings it on top of the catalog if the option for that is selected, but it stays in the hidden threads section. I think both watched and highlighted threads should be unfiltered automatically.

[ccd0]

There should be an option to turn it off (highlight but not unhide) for #1118 (comment).

And I think it would be better to have unhiding via the button/menu stick rather than have watching threads unhide them. That way it will be possible to monitor a thread for replies without having it show up in the index.

Otherwise, it sounds good.