[editing] "beforeinput"/"beforeInput" naming clarification (#116)

http://w3c.github.io/editing/input-events.html#event-type-beforeinput is showing the name as all lower cases `beforeinput`, but other places are showing it as camelCase `beforeInput`.

So which one should `addEventListener(...)` use?

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/editing/issues/116