Migrate RE nickname to JSRE system.

A bunch of relatively advanced features of JSRE getting shown off here, actually...RE Nickname is a pretty complicated beast.

Both entry points work fine (the chained setType call is how we can distinguish them using only event parameters...no globals necessary).

I think this is the first event that actually exploits the variable event weight system...RE Nickname is more likely to fire on more devoted slaves, and it's more likely to fire as a nonindividual event than an individual one. Lots of potential in variable event weighting, it's just not something that existing events do very often.

The "soft refresh" from the "Disapprove" response is also pretty unique so far (and a bit hacky, frankly...not real happy with the regen counter being necessary, but at least it works). I think this'll actually be really uncommon...this event is unusual in that the responses, not just the text, have to be completely regenerated. Might be able to do this a different/cleaner way by hoisting more of the context into this instead of the rendering functions.

All of the responses use the inline-cheat locking mechanism that's so far only been seen in RE Relative Recruiter, too (but I imagine that'll get a bit more widespread as we propagate inline cheat/debug settings to other events).