Unicode character flooding

The following inputs must be sanitized so that it is not used to flood a room.

Here is the link to the characters http://pastebin.com/pKPZC5RX Here are two example images

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These are combining characters, you can read more about them here: http://stackoverflow.com/q/10414864/796832

We can use something like strip-combining-marks to filter out the troubled characters.

@abhisekp pointed out another fix on that SO question which is just to add overflow: hidden; to the message container. While it is an easy fix, not sure if it is the right decision.