add ability to blacklist emotes client-side

[xDashh]

Many people in chat dislike a small sub-set of emotes and really do not want to see them. However, (harsh-)ignoring those is not a good solution since they still want to be able to follow chat.

Add another setting (like highlight or tag), that allows to blacklist emotes, which will henceforth only be displayed by text or hidden completely. (if only one option is implemented, text-only is preferable).